Acute Myocardial Infarction Hospitalizations between Cold and Hot Seasons in an Island across Tropical and Subtropical Climate Zones-A Population-Based Study.

We investigated the effects of cold and hot seasons on hospital admissions for acute myocardial infarction (AMI) at the junction of tropical and subtropical climate zones. The hospitalization data of 6897 AMI patients from January 1997 to December 2011 were obtained from the database of the National Health Insurance, including date of admission, gender, age, and comorbidities of hypertension, diabetes mellitus (DM), and dyslipidemia. A comparison of AMI prevalence between seasons and the association of season-related AMI occurrences with individual variables were assessed. AMI hospitalizations in the cold season (cold-season-AMIs) were significantly greater than those in the hot season (OR 1.15; 95% CI 1.10-1.21). In the subtropical region, cold-season-AMIs were strongly and significantly associated with the ≥65 years group (OR1.28; 95% CI 1.11 to 1.48). In the tropical region, cold-season-AMIs, in association with dyslipidemia relative to non-dyslipidemia, were significantly strong in the non-DM group (OR 1.45; 95% CI 1.01 to 2.09) but weak in the DM group (OR 0.74; 95% CI 0.55 to 0.99). The cold season shows increased risks for AMI, markedly among the ≥65 years cohort in the subtropical region, and among the patients diagnosed with either DM or dyslipidemia but not both in the tropical region. Age and comorbidity of metabolic dysfunction influence the season-related incidences of AMI in different climatic regions.

Intermittent Hypoxia Prevents Myocardial Mitochondrial Ca2+ Overload and Cell Death during Ischemia/Reperfusion: The Role of Reactive Oxygen Species.

It has been documented that reactive oxygen species (ROS) contribute to oxidative stress, leading to diseases such as ischemic heart disease. Recently, increasing evidence has indicated that short-term intermittent hypoxia (IH), similar to ischemia preconditioning, could yield cardioprotection. However, the underlying mechanism for the IH-induced cardioprotective effect remains unclear. The aim of this study was to determine whether IH exposure can enhance antioxidant capacity, which contributes to cardioprotection against oxidative stress and ischemia/reperfusion (I/R) injury in cardiomyocytes. Primary rat neonatal cardiomyocytes were cultured in IH condition with an oscillating O2 concentration between 20% and 5% every 30 min. An MTT assay was conducted to examine the cell viability. Annexin V-FITC and SYTOX green fluorescent intensity and caspase 3 activity were detected to analyze the cell death. Fluorescent images for DCFDA, Fura-2, Rhod-2, and TMRM were acquired to analyze the ROS, cytosol Ca2+, mitochondrial Ca2+, and mitochondrial membrane potential, respectively. RT-PCR, immunocytofluorescence staining, and antioxidant activity assay were conducted to detect the expression of antioxidant enzymes. Our results show that IH induced slight increases of O2-· and protected cardiomyocytes against H2O2- and I/R-induced cell death. Moreover, H2O2-induced Ca2+ imbalance and mitochondrial membrane depolarization were attenuated by IH, which also reduced the I/R-induced Ca2+ overload. Furthermore, treatment with IH increased the expression of Cu/Zn SOD and Mn SOD, the total antioxidant capacity, and the activity of catalase. Blockade of the IH-increased ROS production abolished the protective effects of IH on the Ca2+ homeostasis and antioxidant defense capacity. Taken together, our findings suggest that IH protected the cardiomyocytes against H2O2- and I/R-induced oxidative stress and cell death through maintaining Ca2+ homeostasis as well as the mitochondrial membrane potential, and upregulation of antioxidant enzymes.

Intermittent Hypoxia Inhibits Na+-H+ Exchange-Mediated Acid Extrusion Via Intracellular Na+ Accumulation in Cardiomyocytes.

BACKGROUND/AIMS: Intermittent hypoxia (IH) has been shown to exert preconditioning-like cardioprotective effects. It also has been reported that IH preserves intracellular pH (pHi) during ischemia and protects cardiomyocytes against ischemic reperfusion injury. However, the exact mechanism is still unclear. METHODS: In this study, we used proton indicator BCECF-AM to analyze the rate of pHi recovery from acidosis in the IH model of rat neonatal cardiomyocytes. Neonatal cardiomyocytes were first treated with repetitive hypoxia-normoxia cycles for 1-4 days. Cells were then acid loaded with NH4Cl, and the rate of pHi recovery from acidosis was measured. RESULTS: We found that the pHi recovery rate from acidosis was much slower in the IH group than in the room air (RA) group. When we treated cardiomyocytes with Na+-H+ exchange (NHE) inhibitors (Amiloride and HOE642) or Na+-free Tyrode solution during the recovery, there was no difference between RA and IH groups. We also found intracellular Na+ concentration ([Na+]i) significantly increased after IH exposure for 4 days. However, the phenomenon could be abolished by pretreatment with ROS inhibitors (SOD and phenanathroline), intracellular calcium chelator or Na+-Ca2+ exchange (NCX) inhibitor. Furthermore, the pHi recovery rate from acidosis became faster in the IH group than in the RA group when inhibition of NCX activity. CONCLUSIONS: These results suggest that IH would induce the elevation of ROS production. ROS then activates Ca2+-efflux mode of NCX and results in intracellular Na+ accumulation. The rise of [Na+]i further inhibits the activity of NHE-mediated acid extrusion and retards the rate of pHi recovery from acidosis during IH.

Sudden Cardiac Death Associated with Anomalous Origin of the Left Main Coronary Artery from the Right Sinus, with an Intramural Course.

Anomalous origin of the left main coronary artery from the right sinus of Valsalva is extremely rare and can lead to sudden cardiac death. We report a case in which an 18-year-old college student collapsed immediately after a long-distance run of 10 km. After cardiopulmonary resuscitation and electrical shock for ventricular fibrillation, she experienced a return of spontaneous circulation. Cardiac catheterization and cardiac computed tomographic angiography revealed an unusually long intramural course of the left main coronary artery from the right sinus of Valsalva. The young woman underwent a successful unroofing operation for coronary artery correction. She remained asymptomatic upon exercise during 2.5 years of follow-up.

Supervised Phase II Cardiac Exercise Therapy Shortens the Recovery of Exercise Capacity in Patients with Acute Myocardial Infarction.

[Purpose] To investigate the effects of Phase II cardiac exercise therapy (CET) on exercise capacity and changes in coronary risk factors (CRFs) of patients with acute myocardial infarction (AMI). [Subjects] Thirty male subjects with AMI were divided into an experimental group (EG) and a control group (CG). Another 30 age-matched subjects with patent coronary arteries served as a normal-control group (NCG). [Methods] Subjects in EG (n=20) trained using a stationary bicycle for 30 min at their target heart rate twice a week for 8 weeks. Exercise capacity was defined as the maximal metabolic equivalents (METs) that subjects reached during the symptom-limited maximal exercise test. HR, BP and RPP were recorded. Subjects in EG and CG received exercise tests and screening for CRFs at the beginning of, end of, and 3 months after Phase II CET, while subjects in NCG participated only in the 1st test. [Results] METs of CG did not improve until the 3rd test, while RPP at the 2nd test showed a significant increase. However, EG showed increased METs at the 2nd test without increase of RPP, and increased their high density lipoprotein cholesterol (HDL-C) during the follow-up period between the 2nd and 3rd tests. [Conclusion] Phase II CET shortens the recovery time of exercise capacity, helps to maintain the gained exercise capacity and increases HDL-C in phase III.

N-terminal pro-B-type natriuretic peptide is inversely associated with metabolic syndrome in hypertensive patients.

BACKGROUND: It has been shown that metabolic syndrome is associated with lower levels of plasma N-terminal pro-B-type natriuretic peptide (Nt-proBNP) in the general population. However, there is no study about the association between Nt-proBNP and metabolic syndrome in hypertensive patients. AIM: : To elucidate the relationship between Nt-proBNP and components of metabolic syndrome in hypertensive patients. METHODS: Fasting blood samples were obtained from 74 hypertensive patients in our institution. Plasma levels of Nt-proBNP and other biochemical data were measured. Metabolic syndrome and its components were defined using diagnostic criteria from the International Diabetes Federation. RESULTS: Forty-four hypertensive patients met the criteria for metabolic syndrome. We found that plasma Nt-proBNP levels were lower in hypertensive patients with metabolic syndrome attributable to inverse relationships between Nt-proBNP and albumin, triglyceride, insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and pancreatic ß-cell function (HOMA-ß). We further performed a multivariable linear regression analysis. The result showed that HOMA-IR is the independent predictor of plasma Nt-proBNP levels in hypertensive patients. CONCLUSIONS: Plasma Nt-proBNP levels are inversely associated with metabolic syndrome in hypertensive patients. HOMA-IR is the independent predictor of Nt-proBNP in hypertensive patients.

N-terminal pro-B-type natriuretic peptide level inversely associates with metabolic syndrome in elderly persons.

AIMS: Serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) was lower in the general population with metabolic syndrome (MetS). The aim of this study was to evaluate the relationship between MetS and fasting serum NT-proBNP concentration in elderly persons. METHODS: Fasting blood samples were obtained from 84 elderly volunteers aged 65 years or older. MetS and its components were defined using diagnostic criteria from the International Diabetes Federation. RESULTS: Thirty-eight elderly persons (45.2%) had MetS. Fasting NT-proBNP level was negatively correlated with MetS among elderly patients (p = 0.001). Univariate linear regression analysis showed that age (r = 0.338; p = 0.002) was positively correlated with fasting serum log-NT-proBNP levels, while height (r = -0.253; p = 0.020), body weight (r = -0.238; p = 0.029), waist circumference (r = -0.270; p = 0.013), body fat mass (r = -0.356; p = 0.002) and triglyceride (r = -0.291; p = 0.007) were negatively correlated with fasting serum log-NT-proBNP levels among the elderly persons. Multivariate forward stepwise linear regression analysis of the significant variables showed that age (R2 change = 0.114, p = 0.011), triglyceride (R2 change = 0.118, p < 0.001), body fat mass (R2 change = 0.084, p < 0.001), and height (R2 change = 0.101, p < 0.001) were the independent predictor of fasting serum log-NT-proBNP levels in elderly persons. CONCLUSIONS: NT-proBNP level is significantly reduced in elderly persons affected by MetS, and is significantly positively related to age, while negatively related to triglyceride, body fat mass, height in these subjects.

Serum atrial natriuretic peptide level inversely associates with metabolic syndrome in older adults.

AIM: Atrial natriuretic peptide (ANP) is a potent lipolytic agent that acts in adipose tissue. Low levels of ANP might lead to reduced lipolysis and excessive weight gain, which could be one of the biological alterations that contribute to the development of obesity. The aim of the present study was to evaluate the relationship between metabolic syndrome and fasting serum ANP concentrations in older adults. METHODS: Fasting blood samples were obtained from 90 older adults. Metabolic syndrome and its components were defined using diagnostic criteria from the International Diabetes Federation. RESULTS: A total of 40 older adults (44.4%) had metabolic syndrome. Fasting ANP level was negatively correlated with metabolic syndrome (P = 0.015). Univariate linear regression analysis showed that high-density lipoprotein cholesterol (P < 0.001) was positively correlated with serum logANP levels, whereas waist circumference (P = 0.001) and body fat mass (P = 0.002) were negatively correlated with fasting serum logANP levels. Multivariate forward stepwise linear regression analysis of the significant variables showed that high-density lipoprotein cholesterol (ß = 0.419, R(2) = 0.268, P < 0.001) and body fat mass (ß = -0.396, R(2) = 0.154, P = 0.002) were independent predictors of fasting serum logANP levels in geriatric persons. CONCLUSIONS: Serum ANP levels were reduced in geriatric persons affected by metabolic syndrome. Body fat mass and high-density lipoprotein cholesterol were independent predictors of fasting serum ANP levels in older adults.

Clinical Characteristics and In-Hospital Prognosis of Infective Endocarditis in Two Eastern Counties of Taiwan.

BACKGROUND: Infective endocarditis (IE) is a common and potentially serious disease. Although it is an illness that affects populations around the world, narrower descriptions of this disease as it impacts specific regions are uncommon. We analyzed the clinical characteristics of IE patients from two eastern counties in Taiwan and studied the relationship between the isolated pathogens and clinical outcomes in these patients. METHODS: This is a retrospective chart review study which enrolled patients who received services between January 2007 and December 2010. Subsequent to chart review, IE was confirmed in a total of 55 patients by the modified Duke criteria. RESULTS: Of these patients, 17 (31%) had previous traumatic open skin wounds. Pre-existing cardiac abnormalities were found in 47 (85%) patients, 28 of whom had valvular abnormalities. Staphylococcus aureus was isolated from the blood as the leading pathogen in 25 (45%) patients (including 23 methicillin-sensitive and 2 methicillin-resistant). Septic emboli and shock occurred in 27 (49%) of 55 patients; surgery was performed on 11 (20%) of those patients, and 4 (36%) of them died post-operatively. The total in-hospital mortality rate was 40% (n = 22). Staphylococcus aureus infection was associated with significantly higher complication and mortality rate than non-Staphylococcus aureus infection (59% vs. 41% and 64% vs. 36%, respectively; p < 0.05). In addition, patients with complications had a very high mortality rate (81.5%). CONCLUSIONS: We found that Staphylococcus aureus was the most common pathogen of IE in Eastern Taiwan, and was associated with higher rates of morbidities and mortality. KEY WORDS: Infective endocarditis; Septic shock; Staphylococcus aureus; Systemic embolization.

Inverse association of N-terminal pro-B-type natriuretic peptide with metabolic syndrome in patients with congestive heart failure.

BACKGROUND: Metabolic syndrome has been shown to be associated with lower levels of plasma N-terminal pro-B-type natriuretic peptide (Nt-proBNP) in the general population. We sought to elucidate the relationship between Nt-proBNP and components of metabolic syndrome in patients with congestive heart failure (CHF). METHODS: Fasting blood samples were obtained from 93 patients in our institution. Plasma levels of Nt-proBNP and other biochemical data were measured. The New York Heart Association (NYHA) classification system (I-IV) was used to define the functional capacity of CHF. Metabolic syndrome and its components were defined using diagnostic criteria from the International Diabetes Federation. RESULTS: Forty-nine patients (52.7%) had CHF. There was a positive correlation between plasma Nt-proBNP levels and NYHA functional capacity in CHF patients. Plasma Nt-proBNP levels increased significantly with each increasing NYHA class of the disease. The prevalence of metabolic syndrome in CHF patients was higher than that in patients without CHF. Most importantly, we found that plasma Nt-proBNP levels were lower in CHF patients with metabolic syndrome attributable to inverse relationships between plasma Nt-proBNP and body mass index (ß = -0.297), plasma triglyceride (ß = -0.286) and homeostasis model assessment of insulin resistance (HOMA-IR; ß = -0.346). Fasting glucose to insulin ratio (FGIR, an insulin sensitivity index) was positively associated with plasma Nt-proBNP levels (ß = 0.491), and was the independent predictor of plasma Nt-proBNP levels in CHF patients. CONCLUSIONS: Plasma Nt-proBNP levels are inversely associated with metabolic syndrome in CHF patients. Reduced plasma Nt-proBNP levels in CHF patients may lead to impaired lipolysis and metabolic function, and may contribute to the development of metabolic syndrome in CHF patients.

Diffuse plexus-like coronary artery-left ventricular fistulae leading to coronary steal syndrome: a pattern of anomalous coronary microvascularization.

Coronary artery fistulae that drain into the left ventricle are extremely rare, and even fewer cases of fistulae involving all three of the coronary arteries have so far been reported. We herein report a 64-year-old woman with a unique pattern of coronary artery-left ventricular fistulae that involved all three of the coronary arteries. The multiple fistulae presented in a diffuse plexus-like arrangement. The fistulae resulted in a diastolic volume overload of the left ventricle (left-to-left shunt), as well as "coronary steal" with the shunting of blood away from the myocardium since the fistulae represented the path of least resistance.

Inverse association of long-acting natriuretic peptide with metabolic syndrome in congestive heart failure patients.

AIMS: Long-acting natriuretic peptide (LANP) is one of the peptide hormones in atrial natriuretic peptide (ANP) pro-hormone. Low levels of natriuretic peptide may lead to reduced lipolysis and excessive weight gain in obese patients. The aim of this study was to investigate the relationship between fasting serum LANP level and the metabolic syndrome (MetS) among congestive heart failure (CHF) patients. METHODS: Fasting blood samples were obtained from 186 patients with normal renal function in cardiac clinic outpatients. CHF defined by the American College of Cardiology Foundation and the American Heart Association 2005 Guidelines. MetS and its components were defined using diagnostic criteria from the International Diabetes Federation. RESULTS: Ninety-eight patients (52.7%) had CHF. There was a tendency of increased fasting LANP levels as the NYHA CHF functional classes increased (p = 0.002). Forty-six of the CHF patients (46.9%) had MetS. Fasting LANP level negatively correlated with MetS among CHF patients (p < 0.001). Univariate linear regression analysis showed that BUN (p = 0.026) positively correlated with fasting serum LANP levels, while body weight (p = 0.009), BMI (p = 0.004), homeostasis model assessment of insulin resistance (HOMA-IR; p = 0.024) and HOMA-ß (p = 0.001) negatively correlated with fasting serum LANP levels among the CHF patients. Multivariate forward stepwise linear regression analysis of the significant variables showed that the HOMA-ß (R2 change = 0.292, p < 0.001) and HOMA-IR (R2 change = 0.081, p = 0.019) were independent predictors of fasting serum LANP levels in CHF patients. CONCLUSIONS: LANP level is significantly reduced in CHF patients affected by MetS. HOMA-ß and HOMA-IR were independent predictors of serum LANP levels in CHF patients.

Low serum long-acting natriuretic peptide level correlates with metabolic syndrome in hypertensive patients: a cross-sectional study.

BACKGROUND AND AIMS: Long-acting natriuretic peptide (LANP) is one of the peptide hormones in atrial natriuretic peptide (ANP) prohormone. Its biological properties are blood pressure regulation, maintenance of plasma volume and anticancer effects. The aim of this study was to evaluate the relationship between metabolic syndrome (MetS) and fasting serum LANP concentration in hypertensive patients. METHODS: Fasting blood samples were obtained from 224 patients with or without hypertension. MetS and its components were defined using diagnostic criteria from the International Diabetes Federation. RESULTS: Eighty-eight hypertensive patients (59.5 %) had MetS. Hypertensive patients with MetS had higher body weight (p = 0.003), waist circumference (p = 0.003), body mass index (p = 0.002), triglyceride concentrations (p = 0.029), insulin levels (p = 0.001), HOMA-IR (p <0.003) and HOMA-ß (p = 0.049) and lower HDL-C concentrations (p = 0.001), LANP levels (p = 0.012) than those without MetS. The univariable linear regression analysis showed that age (p = 0.038) and the BUN concentration (p = 0.022) were positively correlated with the serum LANP levels, whereas the insulin level (p = 0.001), HOMA-IR (p = 0.004), and HOMA-ß (p = 0.001) were negatively correlated with the fasting serum LANP levels among the hypertensive patients. Multivariable forward stepwise linear regression analysis of the significant variables showed that the HOMA-ß (ß = -0.387, R(2) = 0.141, p <0.001) was an independent predictor of fasting serum LANP levels in hypertensive patients. CONCLUSIONS: LANP level is significantly reduced in hypertensive patients affected by MetS and is negatively related to pancreatic beta cell function in hypertensive patients.

Effects of Combined Phase III and Phase II Cardiac Exercise Therapy for Middle-aged Male Patients with Acute Myocardial Infarction.

[Purpose] To investigate the effects of cardiac exercise therapy (CET) on exercise capacity and coronary risk factors (CRFs) of patients with acute myocardial infarction (AMI). [Methods] Patients who participated in an 8-week supervised, hospital-based phase II and 6-month home-based phase III CET with monthly telephone and/or home visits were defined as the exercise group (EG) (n=20), while those who did not receive phase II or phase III CET were defined as the no-exercise group (NEG) (n=10). CRFs were evaluated pre- and post-phase II and eight months after discharge. One and two-way repeated measures ANOVA were used to perform intra- and inter-group comparisons. [Results] Thirty men with AMI aged 49.3 ± 8.3 years were studied. EG increased their exercise capacity (METs) (6.8 ± 1.6 vs.10.0 ± 1.9) after phase II CET and was able to maintain it at 8-month follow-up. Both groups had significantly fewer persons who kept on smoking compared to the first examination. High density lipoprotein cholesterol (HDL-C) increased from 38.1 ± 11.0 to 43.7 ± 8.7 mg/dl at follow-up in EG while no significant difference was noted in NEG. [Conclusion] After phase III CET subjects had maintained the therapeutic effects of smoking cessation, and increasing exercise capacity obtained in phase II CET. HDL-C in EG continued to improve during phase III CET.