Chronic Heart Conditions Research Articles

Dynamic Action Potential Clamp Investigation of Pro-Arrhythmic Risk of Drugs Binding to hERG Potassium Channels

Many commonly used drugs can bind to and block the hERG channel and cause the potentially life threatening acquired long-QT syndrome.Whilst obtaining an IC50 for drug block of hERG is relatively straight forward, this is a poor surrogate for risk of pro-arrhythmia. Predicting the overall consequences of hERG drug block on cardiac electrical activity is complicated by the fact that the effect of hERG channel block varies in different cells (e.g. epicardial, mid-myocardial, endocardial, Purkinje) of the heart. Furthermore it is significantly altered by the electrical remodeling that occurs in many chronic heart conditions. With the aging of our population and an increasing proportion of people with chronic heart conditions it is especially important to understand how disease states affect the consequences of hERG drug block and risk of pro-arrhythmia.Here we describe a recently developed dynamic action potential clamp system (dAPC) to investigate the effect of hERG block on cardiomyocytes. The system consists of conventional whole cell voltage clamp study of ion channels in mammalian expression systems, coupled to a real time computer model of human cardiomyocyte action. The dAPC system integrates the current recordings from a patch clamped cell into an in-silico cell model, the output of which is then used to determine the voltage of the patch clamped cell. When used in combination with a state of the art drug perfusion system this integrative approach will permit testing of drugs on specified ion channels in a physiologically relevant environment, something that is not possible with conventional patch clamp methods.

Caseous calcification of the mitral annulus — A clinical case

Introduction: The caseous calcification of the mitral annulus is a rare form of calcification not totally understood and which could point to an incorrect diagnosis of intracardiac tumor, leading to unnecessary surgeries. The typical picture in the echocardiogram is an hyperechogenic round mass in the outside and an hypoechogenic area inside. The course of the disease is benign,making the intervention dependent on themitral insufficiency that eventually will cause. Clinical case: Caucasian, 63 year old female, history of hypertension, venous insufficiency and nonspecific valvular disease, poli-medicated, admitted in the InternalMedicineWard with aggravation of chronic heart failure due to unknown cause. In the Ward, the full clinical history of the patientwas taken, and the symptoms were a lower respiratory infection with a week of evolution, which aggravated the chronic heart condition. The physical exam revealed: edemas in the lower limbs to the knee level, and crackles and rhonchi on the pulmonary auscultation. The patientwas treatedwith antibiotics for a respiratory infection acquired in the community and diuretics, while waiting to perform further exams. In the blood screen the Pro-BNP was increased, along with the inflammatory cells and CRP. Chest X-Ray was normal and the Echocardiogram revealed mitral e tricuspid insufficiency with calcification of the mitral valve due to a mass, which was suggested with the realization of a CT scan. Instead of a CT, a Cardiac MRI was performed revealing an intracardiac mass in the mitral valve, suspicious of a tumor or caseous calcification of the mitral valve. The case was discussed with the cardiothoracic surgery department, the patient recovered well with no need of surgery for now. Discussion: The presence of a caseous calcification of the mitral annulus is a common echocardiogram finding, especially in women in their 60's. The detection of intracardiac masses in the echocardiogram is an accidental finding or could be discovered on the follow-up of patients with chronic heart failure or thromboembolic conditions. The caseous calcification of the mitral annulus is a chronic and degenerative process, followed by the fibrosis of themitral valve withmain involvement of the posterior leaflet andmitral annulus. A Trans-thoracic Echocardiogram is an excellent noninvasive technique for the diagnosis of this disease and the images should be known. A Trans-esophageal Echocardiogram is superior for the evaluation of the etiology, the masses seen the in the echocardiogram look similar to those found in Cardiac CT orMRI.Conclusion: The caseous calcification of themitral annulus is a rare clinical situation, foundmainly in patients in the six decade of life or older, and should be integrated in the differential diagnosis upon the detection of an hyperechogenic mass in the posterior part of themitral valve annulus in echocardiogram. Upon the confirmation of the echocardiographic findings, the patients only have surgical indication if the hemodynamic state is compromised along with mitral valve function and not by the mass itself, which is totally benign.

THE EFFECT OF TELEPHONE SUPPORT INTERVENTIONS ON CORONARY ARTERY DISEASE (CAD) PATIENT OUTCOMES DURING CARDIAC REHABILITATION: A SYSTEMATIC REVIEW AND META-ANALYSIS

BackgroundCardiac rehabilitation is offered to individuals after cardiac events to aid recovery and reduce the likelihood of further cardiac illness. However, patient participation remains suboptimal and the provision of high...

Recent Trends in Veterans Affairs Chronic Condition Spending

The change in prevalence and total Veterans Affairs (VA) spending were estimated for 16 chronic condition categories between 2000 and 2008. The drivers of changes in spending also were examined. Chronic conditions were identified through diagnoses in encounter records, and treatment costs per patient were estimated using VA cost data and regression models. The estimated differences in total VA spending between 2000 and 2008 and the contributions of population increase, differences in prevalence, and differences in treatment costs were evaluated. Most of the spending increases during the study period were driven by the increase in the VA patient population from 3.3 million in 2000 to 4.9 million in 2008. Spending on renal failure increased the most, by more than $1.5 billion, primarily because of higher prevalence. Higher treatment costs did not contribute much to higher spending; lower costs per patient for several conditions may have helped to slow spending for diabetes, chronic obstructive pulmonary disease, heart conditions, renal failure, dementia, and stroke. Lowering treatment costs per patient for common conditions can help slow spending for chronic conditions, but most of the increase in spending in the study period was the result of more patients seeking care from VA providers and the higher prevalence of conditions among patients. As the VA patient population continues to age and to develop more co-morbidities, and as returning veterans seek care for service-related problems, higher spending on chronic conditions will become a more prominent issue for the VA health care system.

Experiences of the Department of Anesthesiology and Intensive Therapy of Semmelweis University during the 2009 pandemic H1N1 (pH1N1) influenza outbreak

Abstract Introduction: The 2009 pandemic 2009 H1N1 (pH1N1) influenza A virus shows a markedly different disease pattern than seasonal strains, causing critical illness in relatively young, female, pregnant individuals as well as in comorbid patients. Materials and methods: The Department of Anesthesiology and Intensive Therapy of Semmelweis University served as a regional influenza center for the adult critically ill during the winter of pH1N1 outbreak. We analyzed data collected from 26 suspected pH1N1 critically ill patients treated in our unit during this period. Results: Sixteen cases were confirmed as pH1N1 infection with RT-PCR, while the other 10 patients with influenza like illness showed tendency to a different age and comorbidity, as well as outcome characteristics, suggesting a different pathogenesis. Confirmed pH1N1 patients showed a mean age of 50.5 years (median: 44; range: 20–85), with female predominancy (69%). Comorbidity was present in 69% of cases (chronic heart conditions, chronic pulmonary disease, previous history of malignancy present in 31; 25 and 19%, respectively). Twenty-five percent of the patients were pregnant women. Nineteen percent of the cases received previous pH1N1 vaccination. But two patients were later readmitted for worsening chronic conditions that led to death, which resulted in a total mortality rate of 31%. Mean APACHE II and SOFA scores on admittance were 12.2 and 5.3, respectively. Average length of treatment was 11.5 days (median: 6.5; range 2–50 days). All patients received ventilatory assistance, 69% of patients received invasive, while 31% of patients received non-invasive ventilatory assistance. The average number of days of invasive ventilation was 10.5 days (median: 5.5; range: 2–45). Forty-five percent of ventilated patients required rescue ARDS therapy. Complications included hemodynamic instability (56%); acute renal failure (13%) and pneumothorax (13%). Superinfection with other microbes were observed in 56% of the patients. Conclusions: In our study, pH1N1 infected critically ill patients had a wide age range, but were more commonly female, pregnant, or had a previously described underlying disease. Mortality, length of treatment, need for invasive mechanical ventilation, length of mechanical ventilation, major complication rates were similar to those previously described. A previously not reported relatively high occurrence of pneumothorax was noted, which is possibly a long-term complication of severe viral pneumonitis.

Barriers to effective self-management in cardiac patients: The patient's experience

Objective This paper identifies common obstacles impeding effective self-management among patients with heart disease and explores how for disadvantaged patients access barriers interfere with typical management challenges to undermine patients’ efforts to care for their illnesses. Methods We convened 33 focus group discussions with heart patients in 10 U.S. communities. Using content analysis, we identified and grouped the most common barriers that emerged in focus group discussions. Results We identified nine major themes reflecting issues related to patients’ ability to care for and manage their heart conditions. We grouped the themes into three domains of interest: (1) barriers that interfere with getting necessary services, (2) barriers that impede the monitoring and management of a heart condition on a daily basis, and (3) supports that enable self-management and improve care. Conclusion For disadvantaged populations, typical problems associated with self-management of a heart condition are aggravated by substantial obstacles to accessing care. Practice implications Ensuring disadvantaged patients with chronic heart conditions are linked to formal systems of care, such as cardiac rehabilitation programs, could better develop patients’ self-management skills, reduce barriers to receiving care and improve the overall health outcomes of these patients.

Implementing the Chronic Care Model: A Statewide Focus on Improving Diabetes Care for Pennsylvania

C hronic diseases represent a significant public health burden by decreasing quality of life and causing death and disability at great economic cost. In Pennsylvania, chronic diseases are the leading cause of death and disability and account for 80% of all health care costs. About half of all Pennsylvanians have a chronic disease, including diabetes, asthma, heart conditions, and others.1 These chronic conditions are exacerbated by obesity, an older population, smoking, and other factors that are hardly unique to the state but statistically more prevalent. Unfortunately, reports also show that only 56% of patients in the state receive the kind of care recommended for chronic disease.2. The primary care system, through which most of chronic care is provided, is insufficiently oriented toward the management and maintenance of the chronically ill.3 Overburdened clinicians do not have ready access to information about their patients or time to meet all of their patients' needs. Furthermore, there is a lack of care coordination and follow-up, and patients often are inadequately trained to manage their disease.3 Primary care practices are also poorly compensated by insurers and government payers under existing reimbursement models. The potential consequences of poor management are grave, and much of the costs would be unnecessary if patients received evidence-based care in a setting in which multiple practitioners can communicate and collaborate. The number of people with diabetes is expected to increase alarmingly in the coming decades. The International Diabetes Federation estimates that more than 250 million people around the world have diabetes. This total is expected to rise to 380 million within 20 years. Each year, an additional 7 million people develop diabetes.4 In the United States, the incidence of diabetes is also growing and nearly doubled between 1995 and 2006 to 7.4% of the population. …

Clinical Patterns of Obstructive Sleep Apnea and Its Comorbid Conditions: A Data Mining Approach

Obstructive sleep apnea often results in a wide range of comorbid conditions. Although some conditions have been clearly identified as comorbid, a full clinical pattern of associated diseases has not been systematically documented. This research aimed to reveal the full pattern of comorbid conditions associated with OSA by employing a data mining technique. A large data repository (the New South Wales inpatient Data Collection) collected between 1999 and 2004 was mined, and all clinical diagnoses were coded with ICD-10-AM codes. A total of 60,197 cases (4% of total records) were identified as related to OSA (72.2% males, 27.8% females). OSA occurrence showed 2 peaks at 0-4 years and 55-59 years. A strikingly low occurrence was observed for the adolescent years. Conditions comorbid with OSA in adults by descending frequency were essential hypertension, obesity, hypercholesterolemia, type 2 diabetes, past or current tobacco use, and ischemic heart conditions. Obesity and OSA showed a similar time course of onset, with a latent period of 5 years for hypertension and type 2 diabetes and 15 years for chronic ischemic heart conditions. Comorbid conditions were predominantly of the cardiovascular, endocrine/metabolic and respiratory systems. The data also indicated OSA patients are high users of health services. The data mining technique confirms the prevalence of the disease, describes the age distribution patterns and time courses of disease development from obesity and OSAto comorbid conditions, and implicates possible interrelationships among these conditions and high cost of treating OSA patients.

Co-morbidities associated with influenza-attributed mortality, 1994–2000, Canada

The elderly and persons with specific chronic conditions are known to face elevated morbidity and mortality risks resulting from an influenza infection, and hence are routinely recommended for annual influenza vaccination. However, risk-specific mortality rates have not been established. We estimated age-specific influenza-attributable mortality rates stratified by the presence of chronic conditions and type of residence based on deaths of persons who were admitted to hospital with a respiratory complication captured in our national database. The majority of patients had chronic heart or respiratory conditions (80%) and were admitted from the community (80%). Influenza-attributable mortality rates clearly increase with age for all risk groups. Our influenza-specific estimates identified higher risk ratios for chronic lung or heart disease than have been suggested by other methods. These estimates identify groups most in need of improved vaccines and for whom the use of additional strategies, such as immunization of household contacts or caregivers should be considered.

Does the value of a statistical life vary with age and health status? Evidence from the US and Canada

This paper provides an empirical assessment of the effects of age and baseline health on willingness to pay (WTP) for mortality risk reductions by reporting the results of two contingent valuation surveys: one administered in Hamilton, Ontario and the other to a national sample of US residents. Respondents for both surveys were limited to persons aged 40 years and older to examine the impact of age on WTP. Using the WTP responses and those regarding respondent's own and family health histories, we find weak support for the notion that WTP declines with age, and then, only for the oldest respondents (aged 70 or above). Furthermore, we find no support for the idea that people with chronic heart or lung conditions, or cancer, are willing to pay less to reduce their risk of dying than people without these illnesses. If anything, people with these illnesses are willing to pay more.

Association of Helicobacter pylori infection with lifestyle, chronic disease, body-indices, and age at menarche in Danish adults.

This study examines the association between lifestyle factors, chronic disease, body-indices, and the seroprevalence of Helicobacter pylori infection in Danish adults. The relationship between age at menarche and H. pylori infection is also assessed. A random sample of 3,608 Danish adults completed a questionnaire about lifestyle factors (smoking habits, alcohol consumption, and coffee and tea intake), doctor diagnosed chronic diseases (heart conditions, diabetes, chronic bronchitis, and hypertension), menarche, and socio-demographic factors. A total of 2,913 participants were eligible for the present study. Electrocardiographs were recorded and blood pressure and serum lipid levels (HDL cholesterol, triglyceride, and cholesterol) were measured. Height and weight were determined and body mass index (BMI) calculated. Sera were analysed with an enzyme-linked immunosorbent assay for the presence of H. pylori specific IgG antibodies. The seroprevalence of H. pylori infection was associated with weekly alcohol intake > or = 6 drinks (odds ratio 0.7, 95% confidence interval 0.6-0.9) due to a low rate of H. pylori infection among wine drinkers (odds ratio 0.6, 95% confidence interval 0.5-0.7). No associations were found with smoking habits or serum lipids. People with upper quartile BMI (> or = 26.8 kg/m2) were more likely to be seropositive for antibodies to H. pylori (odds ratio 1.6, 95% confidence interval 1.1-2.4). Chronic bronchitis (odds ratio 1.6, 95% confidence interval 1.1-2.5) and unspecified heart condition (odds ratio 2.0, 95% confidence interval 1.1-3.3) was more often seen in IgG seropositive women than in uninfected women. The likelihood of being seropositive for IgG antibodies to H. pylori increased with age at menarche (odds ratio per year 1.10, 95% confidence interval 1.02-1.19). Previously reported associations with age and socioeconomic status were confirmed. We conclude that wine drinking is associated with lower rates of H. pylori infection in Danish adults. The seroprevalence of H. pylori infection is increased in people with high BMI. H. pylori infection may relate to a history of late menarche and chronic bronchitis in Danish women.

Chagas disease in the central region of Honduras: knowledge, beliefs, and practices

From November to December 1991 and in March 1993 a survey was conducted in 17 rural communities located in Central Honduras. The communities belonged to two areas where Chagas' disease is endemic. In one of them, disease control activities had been conducted. A total of 849 adults, one in each of an equal number of households, was interviewed. The objective of the survey was to investigate and compare in both locations knowledge about Chagas' disease and its routes of transmission, measures aimed at avoiding the presence of triatomines within households, beliefs surrounding the vector and its control, and the population's sources of information about the disease. A 23-item questionnaire was tested and precoded. Almost 100% of the subjects who were surveyed were able to identify the vector and to describe its habits, but only 30.1% knew that Triatoma is the vector for the disease and only about 6% associated it with a chronic heart condition. Around 47.9% of survey subjects indicated that eliminating triatomines from households is a personal responsibility, although 78% identified as the control measure the institutional application of insecticides. Personal contact between a health worker and community members was the chief source of information for those who mentioned having heard of Chagas' disease (41.0%). These results suggest that health education should be included as a component in the planification of control programs. The role played by triatomines in disease transmission should be emphasized, as well as the importance of carrying out household improvements, with community participation, as an effective and sustainable measure. To achieve greater impact, this component should be developed through interpersonal communication channels.

DOWN BUT NOT OUT

UNLIKE player pianos and Stanley Steamers, tuberculosis is still not a thing of the past. What has happened to the Rose family in the past few years shows why public health workers continue to strive to control the spread of tuberculosis. Redmont may not be the prettiest or sunniest town in California, but it is home to the Rose family-and they like it. The youngest members of the family Warren, Kay, and Larry, 12, 11, and 9 years old respectively, offer no more than the usual complaints about school, and welcome weekends and vacations. Helen, who is 21, likes her job with the telephone company, and 22-year-old Bill, who has become man of house also works. Mrs. Rose does her best to be a good mothershe is often a little sad that her husband did not live long enough to see his children grow up. This was the Rose family when I first knew them. They appeared to be a healthy, happy, fun-loving family. But, the three youngest children had all been hospitalized with active pulmonary tuberculosis and Mrs. Rose had only recently been discharged from a sanatorium. Even now their every activity is geared to a process of living with, or rather in spite of, TB. What was the story five years ago? Mr. Rose was alive at that time but was unable to work because of a chronic heart condition. Warren and Larry were hospitalized because of a fever of unknown origin. At this time the family became known to the local health department and the public health nurse was asked to visit them to obtain necessary epidemiological information. The data she obtained led the doctor to suspect tuberculosis. The chest x-rays of the entire family showed that both boys and Kay had primary tuberculosis, and that Mr. Rose had several calcified areas in his lungs. After several months in the hospital, the children were sent home on a regimen of complete rest. Within a year they all had exacerbations, and had to be rehospitalized. In the meantime Mrs. Rose's chronic asthma became more and more of a problem. Each year it was necessary for her to have an extensive series of antigen injections; many of these were given in the home by the public health nurse. By fall the children were all back in school on restricted activity schedules. Mr. Rose suffered a fatal heart attack, and Mrs. Rose was left with the responsibility of bringing up the family. Throughout this 5-year period the family had routine x-rays and checkups. At the end of that time Mrs. Rose's chest x-ray showed some suspicious shadows. Although her sputum cultures were negative, the doctor thought that she had a small cavity and she was admitted to the sanatorium for a period of rest and treat-