Advances in Electrocardiograms

Electrocardiograms have become one of the most important, and widely used medical tools for diagnosing diseases such as cardiac arrhythmias, conduction disorders, electrolyte imbalances, hypertension, coronary artery disease and myocardial infarction. This book reviews recent advancements in electrocardiography. The four sections of this volume, Cardiac Arrhythmias, Myocardial Infarction, Autonomic Dysregulation and Cardiotoxicology, provide comprehensive reviews of advancements in the clinical applications of electrocardiograms. This book is replete with diagrams, recordings, flow diagrams and algorithms which demonstrate the possible future direction for applying electrocardiography to evaluating the development and progression of cardiac diseases. The chapters in this book describe a number of unique features of electrocardiograms in adult and pediatric patient populations with predilections for cardiac arrhythmias and other electrical abnormalities associated with hypertension, coronary artery disease, myocardial infarction, sleep apnea syndromes, pericarditides, cardiomyopathies and cardiotoxicities, as well as innovative interpretations of electrocardiograms during exercise testing and electrical pacing

The Prognostic Power of the Clinical Exercise Test

Sydän- ja verisuonitauteihin kuolee vuosittain yli 20 000 suomalaista. Tämän vuoksi yhdeksi kansanterveyden suurista haasteista on viime vuosina noussut näiden potilaiden riittävän aikainen tunnistaminen, jotta riittävät hoito- ja tutkimustoimenpiteet saadaan kohdistettua suuren riskin potilaisiin. Kliinistä rasituskoetta ja sen aikaisia ST-segmentin muutoksia EKG:ssä käytetään yleisesti sepelvaltimotaudin diagnostiikassa. Diagnostiikan lisäksi kliinistä rasituskoetta voidaan käyttää myös arvioitaessa potilaan ennustetta sekä sydäntapahtumien riskiä tulevaisuudessa. Aiemmissa tutkimuksissa on todettu, että ST-segmentin muutosten lisäksi kliininen rasituskoe tarjoaa useita muita muuttujia riskinarviointiin. Osana Finnish Cardiovascular Study (FINCAVAS) -tutkimusta väitöskirjatutkimuksessani tutkittiin sekä yksittäisten rasituskokeen aikaisten muuttujien, että eri muuttujien yhdistelmien merkitystä arvioitaessa potilaan ennustetta. FINCAVAS-tutkimusaineisto sisältää kliinisen rasituskokeen aikaiset tiedot 4568 (1765 naista) potilaalta, jotka tulivat vuosien 2001 ja 2008 välisenä aikana kliiniseen rasituskokeeseen Tampereen Yliopistolliseen Sairaalaan ja olivat halukkaita osallistumaan tutkimukseen. Potilaiden seuranta-aika oli keskimäärin 55 kuukautta, jonka aikana kuoli 321 potilasta. Kuolemista 138 oli sydän- ja verisuoniperäisiä, joista edelleen 63 oli sydänäkkikuolemaa. Pienempiä aineistoja otettiin analysoitavaksi lyhyempien seuranta-aikojen jälkeen. Rasituskokeen aikaisen ekg:n lisäksi syke ja verenpaine mitattiin säännöllisesti koko kokeen ajan. Ekg:stä määritettiin sydämen sykevaihtelu (heart rate variability, HRV), T-aallon vuorottelu (T-wave alternans, TWA) sekä PR-intervallit. Väitöskirjatutkimuksessani tutkittiin sekä autonomisen hermoston toimintaa kuvaavia suureita, että sydämen sähköistä toimintaa kuvaavia suureita. Tutkituista suureista rasitusta edeltävän lepovaiheen aikana vaimentunut sydämen sykevaihtelu oli yhteydessä huonoon ennusteeseen usean sykevaihtelua kuvaavan muuttujan osalta. Maksimirasituksen aikainen sydämen sykevaihtelu ei sen sijaan ennustanut kuolleisuutta. Maksimirasituksen aikana T-aallon vuorottelu oli yhteydessä kuolleisuuteen sekä luokiteltuna (?60 ?V) että jatkuvana muuttujana, erityisesti ekg:n kytkennässä V5. Rasituksen jälkeisen palautumisvaiheen aikana T-aallon vuorottelu ?60 ?V oli yhteydessä huonoon ennusteeseen. Myös pidentynyt PR-intervalli sekä ensimmäisen asteen eteiskammiokatkos (AV-katkos) ennustivat sydän- ja verisuoniperäistä kuolleisuutta rasituksen jälkeisen palautumisvaiheen aikana. Hidastunut sykkeen palautuminen (?18 bpm) rasituksen jälkeen oli yhteydessä niin kokonaiskuolleisuuteen kuin sydän- ja verisuoniperäiseen kuolleisuuteenkin. Poikkeuksellisen suuri T-aallon vuorottelu (?60 ?V) yhdistettynä hidastuneeseen sydämen sykkeen palautumiseen oli yhteydessä huonoon ennusteeseen, kun T-aallon vuorottelu oli määritetty joko rasituksen tai palautumisvaiheen aikana. Hidastunut sykepainetulon (rate-pressure product, RPP) palautuminen rasituksen jälkeen oli myös yhteydessä seuranta-ajan kuolleisuuteen. Väitöskirjatutkimukseni perusteella kliininen rasituskoe tarjoaa merkittävästi tietoa arvioitaessa potilaan ennustetta. Uudempiin menetelmiin verrattuna kliininen rasituskoe on edullinen, kajoamaton sekä yleensä helposti saatavilla oleva tutkimus. Diagnostisena testinä rasituskoetta voidaan luotettavasti käyttää vain niille potilaille joiden ennakkotodennäköisyys sepelvaltimotautiin on kohtalainen. Arvioitaessa potilaan ennustetta, kaikki potilaat joiden toimintakyky on riittävä, soveltuvat tutkimukseen. Tämän tutkimuksen perusteella rasituskoe tulisi nähdä kokonaisuutena, johon kuuluvat lepovaihe, rasitus sekä rasituksen jälkeinen palautumisvaihe. Yhdistämällä yksittäisiä muuttujia uusiksi muuttujiksi voidaan rasituskokeen ennustearvoa lisätä ja samalla vähentää virheellisiä riskiarvioita. Kuitenkin tarvitaan vielä uusia ja laajempia tutkimuksia suurilla potilasaineistoilla, ennen kuin voidaan tehdä yleisiä suosituksia rasituskokeen käytöstä riskinarvioinnissa.The more than 20,000 cardiovascular deaths per year in Finland have made the identification of individuals at risk for cardiovascular death a pressing public challenge. The clinical exercise test and exercise-based ST segment deviation are widely accepted methods for diagnosing coronary heart disease (CHD). However, beyond ST segment analysis, a clinical exercise test provides much more information when estimating a patient s risk for future cardiovascular events. As a part of the Finnish Cardiovascular Study (FINCAVAS), the present study was designed to investigate the prognostic power of single and multiple variables derived from a clinical exercise test. The FINCAVAS population includes all patients scheduled for an exercise stress test due to clinical reasons using a bicycle ergometer at Tampere University Hospital and willing to participate in the study between October 2001 and December 2008. The follow-up lasted until September 2009. The final number of participants was 4,568 (1,765 women), but smaller study populations were created after shorter follow-up periods. In addition to repeated measurement of standard parameters such as heart rate and blood pressure, digital high-resolution ECG at 500Hz was recorded continuously during the entire exercise test, including the resting and recovery phases. T-wave alternans (TWA) was analyzed continuously with the time-domain Modified Moving Average (MMA) Method. During the follow-up (55±26 months) 321 patients died, including 138 cardiovascular deaths and 63 sudden cardiac deaths (SCD). The prognostic power of exercise-test-based variables was determined by means of Cox multivariate regression analysis after adjustment for common coronary risk factors. Diminished heart rate variability (HRV) during the pre-exercise phase was associated with an increased risk of all-cause mortality according to several parameters (log VLF power, log LF power, log LF power n.u, log HF power%, pcSD2, log RMSSD), but during peak exercise HRV did not predict worse prognosis. At peak exercise TWA predicted worse prognosis both as a categorized variable (?60 ?V) and a continuous variable, especially in lead V5. During the recovery after exercise TWA ?60 ?V predicted worse prognosis. A prolonged PR interval and first-degree atrioventricular (AV) block during recovery were associated with increased risk of cardiovascular death. Abnormal heart rate recovery (?18 bpm) after exercise was a significant predictor of all-cause death and cardiovascular mortality. The combination of abnormal heart rate recovery and TWA ?60 ?V was a significant predictor of all-cause and cardiovascular mortality when TWA was measured either during peak exercise or during recovery. A decreased recovery of rate-pressure product (RPP) was significantly associated with an increased risk of SCD, cardiovascular mortality and all-cause death. An exercise test utilising the bicycle ergometer has unused prognostic potential when evaluating patients risk for future all-cause and cardiovascular mortality as well as for SCD. To enhance the prognostic power of the exercise test, the test should be considered as a continuum from rest via peak exercise to the recovery phase. Combinations of single parameters can increase the accuracy of the exercise test by reflecting cardiovascular health from several perspectives. However, more studies are needed before universal recommendations for exercise testing in risk stratification can be constructed

Association of eating patterns with blood pressure and body mass index: the INTERMAP study

Background Epidemiologic evidence is sparse on the role of dietary patterns that may be important drivers of high blood pressure (BP) and body mass index (BMI) levels. Additionally, dietary fibre intake in association with BP and BMI yielded inconsistent results. Objective Investigate the relationships of eating frequency, dietary energy density, diet quality, evening energy intake, GI, GL, and dietary fibre to BP, BMI using cross-sectional data from the INTERnational study on MAcro/micronutrients and blood Pressure (INTERMAP) of 4680 men and women aged 40–59 y from Japan, China, the United Kingdom, and the United States of America. Methods During 4 visits, eight BP, four weight and height measures, four 24-hour dietary recalls, and two 24-hour urine samples were collected. Consumption of all solid foods was aggregated into eating occasions. Nutrient density is expressed using the Nutrient Rich Food index. Multivariable adjusted linear regression models were used to estimate BP and BMI differences per 2SD higher intakes of eating occasions, dietary energy density, Nutrient Rich Food index, evening energy intake, GI, GL, and dietary fibre. Results Compared to participants with <4 eating occasions/24-hours, those with ≥6 eating occasions/24-hours had lower average: systolic BP: 116.4 vs. 121.4 mm Hg; BMI: 27.3 vs. 29.0 kg/m2; total energy: 2127 vs. 2521 kcal/24-hours; dietary energy density: 1.5 vs. 2.2 kcal/g; and higher Nutrient Rich Food index score: 35.1 vs. 26.8. Additionally, insoluble fibre higher by 4 g/1000 was inversely associated with systolic BP (p<0.05), while soluble fibre and GI, GL showed no associations with BP and BMI. Conclusions Results suggest that higher meal frequency may be associated with improved diet quality and lower BP and BMI. Higher intakes of insoluble fibre may contribute to lower BP and BMI. This may have implications for behavioural approaches to controlling high BP levels and the obesity epidemic.Open Acces

Walking training improves systemic and local pathophysiological processes in intermittent claudication

Objective: This study examined the impact of submaximal walking training (WT) on local and systemic nitric oxide (NO) bioavailability, inflammation, and oxidative stress in patients with intermittent claudication (IC). Methods: The study employed a randomised, controlled, parallel group design and was performed in a single centre. Thirty-two men with IC were randomly allocated to two groups: WT (n = 16, two sessions/week, 15 cycles of two minutes walking at an intensity corresponding to the heart rate obtained at the pain threshold interspersed by two minutes of upright rest) and control (CO, n = 16, two sessions/week, 30 minutes of stretching). NO bioavailability (blood NO and muscle nitric oxide synthase [eNOS]), redox homeostasis (catalase [CAT], superoxide dismutase [SOD], lipid peroxidation [LPO] measured in blood and muscle), and inflammation (interleukin-6 [IL-6], C-reactive protein [CRP], tumour necrosis factor α [TNF-α], intercellular adhesion molecules [ICAM], vascular adhesion molecules [VCAM] measured in blood and muscle) were assessed at baseline and after 12 weeks. Results: WT statistically significantly increased blood NO, muscle eNOS, blood SOD and CAT, and muscle SOD and abolished the increase in circulating and muscle LPO observed in the CO group. WT decreased blood CRP, ICAM, and VCAM and muscle IL-6 and CRP and eliminated the increase in blood TNF-α and muscle TNF-α, ICAM and VCAM observed in the CO group. Conclusion: WT at an intensity of pain threshold improved NO bioavailability and decreased systemic and local oxidative stress and inflammation in patients with IC. The proposed WT protocol provides physiological adaptations that may contribute to cardiovascular health in these patients

Racial Differences in Hypertension Claims Rates for Medicaid Patients: Has it Changed Since 1991?

The purpose of this study was to determine whether the racial differences hypertension claim rates for Medicaid patients has changed since 1991. Age-specific and age-adjusted prevalence rates of hypertension in 2015, and the first 2015 claim rates by race and gender were calculated and compared to age-specific and age-adjusted prevalence rates of hypertension in 1991 and the first 1991 claim rates by race and gender. Gender-specific black-to-white risk ratios were also calculated. The comparison reveled that in both study groups, African-American females were more likely than African-American males, or whites of either sex to have hypertension diagnoses. Using Medicaid data from 12 unknown states for the 2015 calculations represented a significant limitations due to the possibility that any, most, or all of the 12 states could be excluded from the stroke belt, as well as the early 20th century phenomena such as the Great Migration, which may have caused underestimation of comparison in the prevalence and incidence of hypertension among Medicaid recipients in 2015; however, significant racial differences in the occurrence of hypertension still existed among them

Abstracts of the UNICAMP Academic Medical Congress (CoMAU), 2019

Abstracts of the UNICAMP Academic Medical Congress (CoMAU), 201

Short term physiological changes secondary to exercise in intermittent claudication : short term physiological changes in claudication

Background: In patients with intermittent claudication (IC), supervised exercise programmes (SEP) improve walking distance and quality of life (QoL); however the mechanisms by which these benefits are achieved remain unclear.Endothelial dysfunction is recognised as a trigger of the atheroinflammatory cascade and subsequent cardiovascular disease. In health, training improves cardiorespiratory physiology, inflammation and endothelial function. Changes in cardiorespiratory physiology, inflammatory markers and endothelial function are contradictory in IC.Objectives: This thesis aimed to assess the impact of SEP on cardiopulmonary physiology, endothelial function and athero-inflammatory markers in patients with IC.Methods: Following local research ethics committee and R & D approval, patients with IC were recruited from outpatient clinic. After providing informed written consent, patients underwent baseline assessment on two separate days.Session 1: participants completed a constant load treadmill test with pre and post exercise ankle brachial pressure indices.Session 2: measured QoL, endothelial function (EndoPAT2000, Itamar, Israel), venepuncture and a cardiopulmonary exercise test (CPET) using cycle ergometry. Participants then underwent a 12 week period of SEP which consisted of circuit training, with re-assessments at six and twelve weeks. The primary outcome measure was a 1.5ml/kg/min improvement in peak VO₂ after six weeks of exercise. Secondary outcomes included changes in endothelial function, quality of life, walking distance and inflammatory markers at both six and twelve weeks.Results: No significant improvements in CPET measurements, endothelial function or inflammation were demonstrated at any time point. Traditional markers of walking ability and QoL demonstrated an improvement by 12 weeks.Conclusions: The underlying mechanism through which exercise improves walking distance remains un-identified. Further work regarding the changes at the cellular level within the muscle is of importance

The associations among depression, social support and racial/ethnic disparities in cardiovascular risk profile membership in the National health and nutritional examination survey: a latent profile analysis

Although rates of morbidity and mortality from cardiovascular disease have improved over the past decades, racial disparities in cardiovascular disease risk have persisted for ethnic and racial minorities. Research seeking to explain these disparities has largely focused on traditional risk factors such as obesity, hypertension, diet, and physical activity. However, a large body of literature has evidenced the psychological and social implications of race on cardiovascular risk. The weathering hypothesis posits that stress associated with racial inequities, racism, and discrimination may cause physiological deterioration among African Americans as early as young adulthood, thus contributing to cardiovascular disease disparities. Allostatic load is widely accepted as a quantitative metric used to study the consequences of weathering. This metric provides researchers with the ability to measure both the acute and long-term outcomes of the stress response. Measurement of allostatic load is based on a set of biomarkers that represent the current status of each physiological system that responds to stress (e.g. hypothalamic-pituitary-adrenal (HPA) axis, cardiovascular system, metabolic processes and the immune system). An algorithm is then used to compute allostatic load by demarcating clinical cut points to dichotomize continuous biological measurement into binary high risk variables (0 = low, 1 = high). This value is then summed to yield an allostatic load score which determines the presence of allostatic load. There are three important limitations to this approach. First, clinical cut points may not capture the full extent of biological risk. Second, categorizing otherwise continuous data results in loss of valuable information captured by the variables used to calculate allostatic load. Third, it is improbable that each biomarker equally contributes to the calculation of an allostatic score. The purpose of this study was to expand the weathering hypothesis by developing cardiovascular risk profiles using latent profile analyses on biomarkers commonly used in allostatic load calculations as an alternative to the traditional algorithm.. In addition, this study examined the relationship between demographic variables (race, age, sex, SES), psychosocial factors (depression, social support) and membership in cardiovascular disease risk profiles. Initial analysis using a national sample of a population age 3 to 85 identified four profile groups; low overall risk, kidney risk, vascular risk, and inflammation risk. Compared to Whites, Hispanics were more likely to exhibit an inflammation risk profile while African Americans were more likely to exhibit both inflammatory and vascular risk profiles. In addition, age, sex, and poverty to income ratio were significant predictors of all risk profiles. When focusing on depression and social support in a sample of individuals 40 years and older, analysis identified two profile groups; a low overall risk profile and an inflammation risk profile. Compared to Whites, African Americans were more likely to be members of the inflammatory risk profile. Further, an increase in depression score significantly increased the odds of an inflammatory risk profile membership. Moreover, the relationship between inflammation risk profile membership and social support (emotional, financial, social network) was examined in which no significant relationship was found. However, analysis revealed that the relationship between depression and inflammatory risk was moderated by emotional support, such that having received emotional support significantly decreased the association between depression and inflammatory risk. Findings from this study suggests that examining cardiovascular risk profiles that account for age, race, sex, and socioeconomic status may be useful for extending the weathering hypothesis and identifying different patterns of risk among those who experience allostatic load. Further understanding of the racial differences in depression and inflammatory risk may be beneficial in eliminating disparities in cardiovascular disease. Results from this project indicate that a higher level of emotional support may be promising strategy to reduce cardiovascular risk

Eating and Swallowing, Oral Health, and Saliva Production

Eating and maintaining optimal nutrition are essential to health and quality of life. In both health and disease, eating is influenced by multiple factors including swallowing, oral health, and saliva production. Perturbations to any, or all, of these inter-related factors may result in consequences that negatively affect the health and wellness of an individual. Eating and swallowing impairment are common symptoms of neurodegenerative diseases such as dementia, and these symptoms are associated with a host of negative sequelae such as malnutrition, dehydration, aspiration pneumonia, and reduced quality of life. The studies reported in this dissertation explored elements of eating and swallowing, saliva production, and saliva modulation in healthy individuals and in persons with Alzheimer’s disease (AD). This dissertation is composed of three studies. First, a scoping review methodology was used to examine literature that addressed autonomic nervous system and/or swallowing dysfunction in individuals with AD. Then, systematic review and meta-analysis methodologies were used to examine a potential effect of aging on saliva production. Finally, a within-subjects methodology was used to examine the modulation of salivary flow by tooth brushing in healthy older adults. In the first study, swallowing dysfunction and autonomic nervous system dysfunction, including salivary flow dysfunction, were found to occur in persons with AD. In the second study, salivary flow was found to be reduced in adults aged 60 years and older who were free of major systemic disease. In the third and final study, the use of manual and electric tooth brushing was found to increase whole salivary flow rates in adults aged 60 years of age and older who were free of major systemic disease. The results of this dissertation have very important implications for the future research and management of eating and swallowing, oral health, and saliva production in a variety of populations, including aging individuals and persons with AD