Prognostic and Safety Implications of Renin-Angiotensin-Aldosterone System Inhibitors in Hypertrophic Cardiomyopathy: A Real-World Observation Over 2,000 Patients

Background and Objectives@#The prognostic or safety implication of renin-angiotensinaldosterone system inhibitors (RASi) in hypertrophic cardiomyopathy (HCM) are not well established, mainly due to concerns regarding left ventricular outflow tract (LVOT) obstruction aggravation. We investigated the implications of RASi in a sizable number of HCM patients. @*Methods@#We enrolled 2,104 consecutive patients diagnosed with HCM in 2 tertiary university hospitals and followed up for five years. RASi use was defined as the administration of RASi after diagnostic confirmation of HCM. The primary and secondary outcomes were all-cause mortality and hospitalization for heart failure (HHF). @*Results@#RASi were prescribed to 762 patients (36.2%). During a median follow-up of 48.1months, 112 patients (5.3%) died, and 94 patients (4.5%) experienced HHF. Patients using RASi had less favorable baseline characteristics than those not using RASi, such as older age, more frequent history of comorbidities, and lower ejection fraction. Nonetheless, there was no difference in clinical outcomes between patients with and without RASi use (log-rank p=0.368 for all-cause mortality and log-rank p=0.443 for HHF). In multivariable analysis, patients taking RASi showed a comparable risk of all-cause mortality (hazard ratio [HR], 0.70, 95% confidence interval [CI], 0.43–1.14, p=0.150) and HHF (HR, 1.03, 95% CI, 0.63–1.70, p=0.900). In the subgroup analysis, there was no significant interaction of RASi use between subgroups stratified by LVOT obstruction, left ventricular (LV) ejection fraction, or maximal LV wall thickness. @*Conclusions@#RASi use was not associated with worse clinical outcomes. It might be safely administered in patients with HCM if clinically indicated.

Association between Bone Mineral Density and Coronary Atherosclerotic Plaque According to Plaque Composition: Registry for the Women Health Cohort for Bone, Breast, and Coronary Artery Disease Study

Background@#Although biological links are unclear, low bone density and atherosclerosis are inversely associated. This study evaluated the association between bone mineral density (BMD) and coronary computed tomographic angiography (CCTA) findings, including coronary artery calcification (CAC) score and the presence, extent, and composition of coronary atherosclerotic plaque (CAP) in asymptomatic women. @*Methods@#A symptomatic women aged ≥40 years (N=2, 100; median age, 52 years; range, 40-80 years) were selected from a retrospective observational cohort and stratified into normal, osteopenia, and osteoporosis groups according to BMD T-score grades. We evaluated CAC score and assessed the presence, extent, and stenosis severity of CAP on CCTA. Additionally, CAP was categorized as calcified, mixed, or non-calcified according to calcified component valiums (>130 Hounsfield units). @*Results@#Osteopenia and osteoporosis were found in 28.8% and 5.3% of participants, respectively. CAC score and CAC severity significantly increased with decreased BMD grades (from normal to osteoporosis). The presence of CAP (overall, 15.6%; normal, 12.6%; osteopenia, 20.2%; osteoporosis, 28.8%; P<0.001) and number of segments with CAP significantly increased with decreased BMD grades. Furthermore, the number of segments with calcified or mixed plaques, excluding non-calcified plaques, increased with decreased BMD grades. Although most associations were attenuated or disappeared after adjusting for age and other covariates, calcified plaques showed a strong and age-independent association with BMD grades. @*Conclusions@#The presence and severity of CAC and CAP were significantly associated with BMD severity in asymptomatic women, particularly for the presence of calcified plaques. Further studies are required to determine the association between vascular calcification and bone health status.

Long-term Prognosis of Mild to Moderate Aortic Stenosis and Coronary Artery Disease

Background@#There is an incomplete understanding of the natural course of mild to moderate aortic stenosis (AS). We aimed to evaluate the natural course of patients with mild to moderate AS and its association with coronary artery disease (CAD). @*Methods@#We retrospectively analyzed 787 patients diagnosed with mild to moderate AS using echocardiography between 2004 and 2010. Cardiac death and aortic valve replacement (AVR) for AS were assessed. @*Results@#A median follow-up period was 92 months. Compared to the general population, patients with mild to moderate AS had a higher risk of cardiac death (hazard ratio [HR], 17.16; 95% confidence interval [CI], 13.65–21.59; P < 0.001). Established CAD was detected in 22.4% and associated with a significantly higher risk of cardiac mortality (adjusted HR, 1.62; 95% CI, 1.04–2.53; P = 0.033). The risk of cardiac death was lower when patients were taking statin (adjusted HR, 0.64; 95% CI, 0.41–0.98; P = 0.041), which was clear only after 7 years. Both patients with CAD and on statin tended to undergo more AVR, but the difference was not statistically significant (the presence of established CAD; adjusted HR, 1.63; 95% CI, 0.51–3.51; P = 0.214 and the use of statin; adjusted HR, 1.86; 95% CI, 0.76–4.58; P = 0.177). @*Conclusion@#Mild to moderate AS does not have a benign course. The presence of CAD and statin use may affect the long-term prognosis of patients with mild to moderate AS.

Long-term Prognosis of Mild to Moderate Aortic Stenosis and Coronary Artery Disease

Background@#There is an incomplete understanding of the natural course of mild to moderate aortic stenosis (AS). We aimed to evaluate the natural course of patients with mild to moderate AS and its association with coronary artery disease (CAD). @*Methods@#We retrospectively analyzed 787 patients diagnosed with mild to moderate AS using echocardiography between 2004 and 2010. Cardiac death and aortic valve replacement (AVR) for AS were assessed. @*Results@#A median follow-up period was 92 months. Compared to the general population, patients with mild to moderate AS had a higher risk of cardiac death (hazard ratio [HR], 17.16; 95% confidence interval [CI], 13.65–21.59; P < 0.001). Established CAD was detected in 22.4% and associated with a significantly higher risk of cardiac mortality (adjusted HR, 1.62; 95% CI, 1.04–2.53; P = 0.033). The risk of cardiac death was lower when patients were taking statin (adjusted HR, 0.64; 95% CI, 0.41–0.98; P = 0.041), which was clear only after 7 years. Both patients with CAD and on statin tended to undergo more AVR, but the difference was not statistically significant (the presence of established CAD; adjusted HR, 1.63; 95% CI, 0.51–3.51; P = 0.214 and the use of statin; adjusted HR, 1.86; 95% CI, 0.76–4.58; P = 0.177). @*Conclusion@#Mild to moderate AS does not have a benign course. The presence of CAD and statin use may affect the long-term prognosis of patients with mild to moderate AS.

Evaluation of Coronary Artery Calcium Progression in Asymptomatic Individuals with an Initial Score of Zero

BACKGROUND AND OBJECTIVES: Coronary artery calcium (CAC) scoring in the asymptomatic population can improve cardiovascular risk prediction. We aimed to assess CAC progression and the impact of coronary risk factors on the CAC progression rate in asymptomatic Korean individuals with a baseline CAC score of zero. METHODS: The study population was derived from the Korea Initiatives on Coronary Artery Calcification (KOICA) registry: a retrospective, single ethnicity, multicenter registry of asymptomatic individuals who underwent CAC scoring as a part of a health checkup. Individuals with at least two CAC scores and an initial score of zero were included. CAC progression was defined as [√CAC score (follow-up) − √CAC score (baseline)] ≥2.5. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk was calculated. RESULTS: Among 6,268 participants (mean age, 48.0±7.1 years; male, 80.5%), 719 (11.5%) experienced CAC progression during follow-up (median, 109 months; interquartile range, 78–208 months). The CAC progression rate was 0.3%, 1.9%, 4.3%, 8.6%, and 16.7% in years 1–5, respectively. The chance of CAC progression at 5 years was 13.1%, 22.0%, and 27.9% for individuals with a 10-year ASCVD risk of <5%, ≥5% but <7.5%, and ≥7.5%, respectively. A multivariable analysis revealed age, male sex, waist circumference, diabetes, and low-density lipoprotein cholesterol level as independently associated with annualized CAC progression (p<0.001, p=0.017, p=0.025, p=0.032, and p=0.003, respectively). CONCLUSIONS: The probability of CAC progression is very low in Korean individuals with a CAC score of zero. However, the risk of CAC progression increases nonlinearly over time, and increases as the 10-year ASCVD risk increases.

Evaluation of Coronary Artery Calcium Progression in Asymptomatic Individuals with an Initial Score of Zero

BACKGROUND AND OBJECTIVES@#Coronary artery calcium (CAC) scoring in the asymptomatic population can improve cardiovascular risk prediction. We aimed to assess CAC progression and the impact of coronary risk factors on the CAC progression rate in asymptomatic Korean individuals with a baseline CAC score of zero.@*METHODS@#The study population was derived from the Korea Initiatives on Coronary Artery Calcification (KOICA) registry: a retrospective, single ethnicity, multicenter registry of asymptomatic individuals who underwent CAC scoring as a part of a health checkup. Individuals with at least two CAC scores and an initial score of zero were included. CAC progression was defined as [√CAC score (follow-up) −√CAC score (baseline)] ≥2.5. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk was calculated.@*RESULTS@#Among 6,268 participants (mean age, 48.0±7.1 years; male, 80.5%), 719 (11.5%) experienced CAC progression during follow-up (median, 109 months; interquartile range, 78–208 months). The CAC progression rate was 0.3%, 1.9%, 4.3%, 8.6%, and 16.7% in years 1–5, respectively. The chance of CAC progression at 5 years was 13.1%, 22.0%, and 27.9% for individuals with a 10-year ASCVD risk of <5%, ≥5% but <7.5%, and ≥7.5%, respectively. A multivariable analysis revealed age, male sex, waist circumference, diabetes, and low-density lipoprotein cholesterol level as independently associated with annualized CAC progression (p<0.001, p=0.017, p=0.025, p=0.032, and p=0.003, respectively).@*CONCLUSIONS@#The probability of CAC progression is very low in Korean individuals with a CAC score of zero. However, the risk of CAC progression increases nonlinearly over time, and increases as the 10-year ASCVD risk increases.

Association of Retinal Artery Occlusion with Subclinical Coronary Artery Disease

BACKGROUND: To evaluate the association between retinal artery occlusion (RAO) and subclinical coronary artery disease (CAD). METHODS: We studied 41 patients with non-arteritic RAO without any history or symptoms of CAD, who had undergone coronary computed tomographic angiography (CCTA) for systemic atherosclerotic evaluation between 2007 and 2012. The age- and gender-matched control group comprised 4-fold subjects who were randomly selected from asymptomatic subjects who underwent CCTA during general health evaluation. Medical records and CCTA findings were compared between RAO patients and control groups. Multiple logistic regression analysis was carried out to assess the risk factors associated with CAD. RESULTS: Cardiovascular risk factors were not significantly different between RAO patients and control groups. RAO patients showed higher coronary artery calcium score than did control subjects (267.9 ± 674.9 vs. 120.2 ± 289.5). On CCTA, the prevalence of obstructive CAD (diameter stenosis ≥ 50%) in RAO patients was significantly higher than that in controls (29% vs. 15%; odds ratio [OR], 3.0). RAO patients demonstrated a significantly higher segment-involvement score (SIS) (2.6 ± 3.0 vs. 1.6 ± 2.4) and segment-stenosis score (SSS) (3.6 ± 4.8 vs. 2.0 ± 3.3) than did controls. After adjustment of associated factors, RAO showed significant association (OR, 3.0) with obstructive CAD and extensive CAD (SIS > 4: OR, 2.8; SSS > 8: OR, 3.4). CONCLUSION: Patients with RAO had a higher prevalence of subclinical obstructive CAD with a more extensive and heavier burden of coronary artery plaques than did age- and gender-matched controls. Physicians should understand the potential risk of CAD in RAO patients.

Diagnostic accuracy of manual office blood pressure measurement in ambulatory hypertensive patients in Korea

BACKGROUND/AIMS@#Currently, office blood pressure (OBP) is the most widely used method of measuring blood pressure (BP) in daily clinical practice. However, data on the diagnostic accuracy of OBP in reference to ambulatory blood pressure (ABP) are scarce in Korea.@*METHODS@#In retrospective and prospective cohorts, manual OBP and ABP measurements were compared among ambulatory hypertensive patients. Hypertension was defined as systolic OBP ≥ 140 mmHg and/or diastolic OBP ≥ 90 mmHg, and systolic ABP ≥ 130 mmHg and/or diastolic ABP ≥ 80 mmHg.@*RESULTS@#In the retrospective cohort (n = 903), the mean OBP1 (before ABP measurement) was higher than ABP in both systolic (138 ± 17 mmHg vs. 123 ± 13 mmHg, p < 0.001) and diastolic (84 ± 12 mmHg vs. 78 ± 11 mmHg, p < 0.001) measurements. Interestingly, there was only a weak correlation between OBP and ABP (r² = 0.038, p < 0.001). The overall discordance rate of OBP compared to ABP, which is the reference method for measuring BP, was 43.9%. The prospective cohort (n = 57) showed similar results. In a subgroup analysis, male patients had higher false negative results (masked or under-treated hypertension) than did female patients (26.1% vs. 17.8%, p = 0.003), whereas female patients had a higher false positive rate (white-coat or over-treated hypertension) than did male patients (28.7% vs. 15.2%, p < 0.001).@*CONCLUSIONS@#The diagnostic accuracy of manual OBP is low in reference to ABP. Men and women have different patterns of discordance. These findings indicate that management of hypertensive patients with manual OBP measurements may be suboptimal and encourages the use of ABP in ambulatory hypertensive patients.

Bullous hemorrhagic dermatosis due to enoxaparin use in a bullous pemphigoid patient

Adverse reactions of subcutaneous low molecular weight heparin or unfractionated heparin could be complications by bleeding, heparin-induced thrombocytopenia, drug-induced liver injury, osteoporosis, and cutaneous reactions. Heparin-induced skin lesions vary from allergic reactions like erythema, urticaria, eczema to intradermal microvascular thrombosis associated with heparin-induced thrombocytopenia. There is a rare cutaneous complication, called bullous hemorrhagic dermatosis. We experienced this rare case of the cutaneous complication caused by enoxaparin. Several tense bullous hemorrhagic lesions occurred after 3 days of enoxaparin in a known bullous pemphigoid patient who had aortic valve replacement surgery with a mechanical prosthesis. The bullous hemorrhagic lesions were regressed after the discontinuation of enoxaparin but recurred after re-administration. The lesions were controlled by the administration of systemic corticosteroid and alternative anticoagulant. To date, less than 20 cases have been reported worldwide. This is the first case of bullous hemorrhagic dermatosis induced by enoxaparin, a low-molecular-weight heparin in Korea. This is also the first case of bullous hemorrhagic dermatosis in a known bullous pemphigoid patient.

Differences in the Clinical Characteristics of Rapid Response System Activation in Patients Admitted to Medical or Surgical Services

Variability in rapid response system (RRS) characteristics based on the admitted wards is unknown. We aimed to compare differences in the clinical characteristics of RRS activation between patients admitted to medical versus surgical services. We reviewed patients admitted to the hospital who were detected by the RRS from October 2012 to February 2014 at a tertiary care academic hospital. We compared the triggers for RRS activation, interventions performed, and outcomes of the 2 patient groups. The RRS was activated for 460 patients, and the activation rate was almost 2.3 times higher for surgical services than that for medical services (70% vs. 30%). The triggers for RRS activation significantly differed between patient groups (P = 0.001). They included abnormal values for the respiratory rate (23.2%) and blood gas analysis (20.3%), and low blood pressure (18.8%) in the medical group; and low blood pressure (32.0%), low oxygen saturation (20.8%), and an abnormal heart rate (17.7%) in the surgical group. Patients were more likely classified as do not resuscitate or required intensive care unit admission in the medical group compared to those in the surgical group (65.3% vs. 54.7%, P = 0.045). In multivariate analysis, whether the patient belongs to medical services was found to be an independent predictor of mortality after adjusting for the modified early warning score, Charlson comorbidity index, and intervention performed by the RRS team. Our data suggest that RRS triggers, interventions, and outcomes greatly differ between patient groups. Further research is needed to evaluate the efficacy of an RRS approach tailored to specific patient groups.

Additive Role of Coronary Magnetic Resonance Angiography for the Evaluation of Coronary Artery Disease

Coronary magnetic resonance angiography (CMRA) allows a noninvasive assessment of the coronary anatomy without exposing the patients to radiation. It is also superior to coronary computed tomography angiography (CCTA) for the evaluation of luminal narrowing in heavily calcified coronary segments. We report a case with triple-vessel disease, but it could not be accurately assessed by CCTA because of calcification and lack of a significant perfusion defect or myocardial scarring on cardiac magnetic resonance imaging (MRI). However, whole-heart CMRA performed as part of the cardiac MRI protocol demonstrated significant triple-vessel disease with left main involvement, confirmed by subsequent invasive angiography with a fractional flow reserve measurement.

A novel c.563 T>G, p.L189R lamin A/C mutation in identical twins with dilated cardiomyopathy

No abstract available.

Echocardiographic Predictors for Left Ventricular Remodeling after Acute ST Elevation Myocardial Infarction with Low Risk Group: Speckle Tracking Analysis

BACKGROUND: We sought to assess echocardiographic predictors of left ventricular (LV) adverse remodeling after successfully reperfused acute ST elevation myocardial infarction (STEMI). LV remodeling is commonly found in STEMI patients and it may suggest adverse outcome in acute myocardial infarction. We sought to identify whether 2D strain and torsion be independent parameters for prediction of LV adverse remodeling. METHODS: We investigated 208 patients with low-risk STEMI patients who had follow up echocardiography at 6 or more months. After clinical assessments, all patients received revascularization according to current guideline. LV remodeling was defined as > 20% increase in end-diastolic volume (EDV) at follow up. RESULTS: During the follow-up (11.9 ± 5.3 months), 53 patients (25.5%) showed LV remodeling. In univariate analysis, EDV, end-systolic volume, deceleration time (DT), CK-MB, and global longitudinal strain (GLS) were associated with LV remodeling. In multivariate analysis, EDV [hazard ratio (HR): 0.922, 95% confidence interval (CI): 0.897-0.948, p< 0.001], GLS (HR: 0.842, 95% CI: 0.728-0.974, p = 0.020), DT (HR: 0.989, 95% CI: 0.980-0.998, p = 0.023) and CK-MB (HR: 1.003, 95% CI: 1.000-1.005, p = 0.033) independently predicted LV remodeling. However, global circumferential strain, net twist, and twist or untwist rate were not associated with remodeling. CONCLUSION: Of various parameters of speckle strain, only GLS predicted adverse remodeling in STEMI patients.

Eosinophilic myocarditis: case series and literature review

Eosinophilic myocarditis is a condition resulting from various eosinophilic diseases, including helminth infection, drug hypersensitivity, systemic vasculitis or idiopathic hypereosinophilic syndromes. Clinical manifestations of eosinophilic myocarditis may vary from early necrosis to endomyocardial fibrosis. Eosinophilic myocarditis is one of the most fatal complications of hypereosinophilia. However, eosinophilic myocarditis has been rarely reported in the literature, particularly in Asia Pacific regions, reflecting the under-recognition of the disease among clinicians. Early recognition is crucial for improving clinical outcomes of eosinophilic myocarditis. Early administration of systemic corticosteroid is necessary in eosinophilic myocarditis regardless of underlying causes, as delayed treatment may result in fatal outcomes. In addition, differential diagnoses of underlying causes for eosinophilia are necessary to improve long-term outcomes.

Prognostic Value of Renal Function for Cardiac Events in Patients Without Significant Stenosis on Coronary Computed Tomography Angiography

This study was conducted to determine clinical parameters predicting future major adverse cardiovascular events (MACEs) in patients without significant stenosis on coronary computed tomographic angiography (CCTA). A total of 625 patients with suspected coronary artery disease (CAD) who underwent CCTA that revealed insignificant ( 90 days after CCTA) revascularization were assessed. During the mean follow-up period of 819 +/- 529 days (median 837 days), there were 28 cases of MACEs (4.5%). In multivariable Cox regression analysis, independent predictors for MACEs were male sex (hazard ratio [HR], 2.40; 95% confidence interval [CI], 1.01-5.69; P = 0.046) and low estimated creatinine clearance (eCCr) (< 60 mL/min/1.73 m2) (HR, 3.07; 95% CI, 1.22-7.74; P = 0.017). Low eCCr was the only independent predictor for hard events including cardiac death and MI (HR, 17.6, 95% CI, 1.44-215.7; P = 0.025). In conclusion, renal function is an independent predictor for cardiovascular events among patients without significant CAD by CCTA. Careful monitoring and preventive strategy are warranted in patients with impaired renal function even without significant CAD.

2014 Korean Guidelines for Appropriate Utilization of Cardiovascular Magnetic Resonance Imaging: A Joint Report of the Korean Society of Cardiology and the Korean Society of Radiology

Cardiac magnetic resonance (CMR) imaging is now widely used in several fields of cardiovascular disease assessment due to recent technical developments. CMR can give physicians information that cannot be found with other imaging modalities. However, there is no guideline which is suitable for Korean people for the use of CMR. Therefore, we have prepared a Korean guideline for the appropriate utilization of CMR to guide Korean physicians, imaging specialists, medical associates and patients to improve the overall medical system performances. By addressing CMR usage and creating these guidelines we hope to contribute towards the promotion of public health. This guideline is a joint report of the Korean Society of Cardiology and the Korean Society of Radiology.

2014 Korean Guidelines for Appropriate Utilization of Cardiovascular Magnetic Resonance Imaging: A Joint Report of the Korean Society of Cardiology and the Korean Society of Radiology

Cardiac magnetic resonance (CMR) imaging is now widely used in several fields of cardiovascular disease assessment due to recent technical developments. CMR can give physicians information that cannot be found with other imaging modalities. However, there is no guideline which is suitable for Korean people for the use of CMR. Therefore, we have prepared a Korean guideline for the appropriate utilization of CMR to guide Korean physicians, imaging specialists, medical associates and patients to improve the overall medical system performances. By addressing CMR usage and creating these guidelines we hope to contribute towards the promotion of public health. This guideline is a joint report of the Korean Society of Cardiology and the Korean Society of Radiology.

Successful Implementation of a Rapid Response System in the Department of Internal Medicine / 대한구급학회지

BACKGROUND: A rapid response system (RRS) aims to prevent unexpected patient death due to clinical errors and is becoming an essential part of intensive care. We examined the activity and outcomes of RRS for patients admitted to our institution's department of internal medicine. METHODS: We retrospectively reviewed patients detected by the RRS and admitted to the medical intensive care unit (MICU) from October 2012 through August 2013. We studied the overall activity of the RRS and compared patient outcomes between those admitted via the RRS and those admitted conventionally. RESULTS: A total of 4,849 alert lists were generated from 2,505 medical service patients. The RRS was activated in 58 patients: A (Admit to ICU), B (Borderline intervention), C (Consultation), and D (Do not resuscitate) in 26 (44.8%), 21 (36.2%), 4 (6.9%), and 7 (12.1%) patients, respectively. Low oxygen saturation was the most common criterion for RRS activation. MICU admission via the RRS resulted in a shorter ICU stay than that via conventional admission (6.2 vs. 9.9 days, p = 0.018). CONCLUSIONS: An RRS can be successfully implemented in medical services. ICU admission via the RRS resulted in a shorter ICU stay than that via conventional admission. Further study is required to determine long-term outcomes.

Left Atrial Mechanical Function and Stiffness in Patients with Paroxysmal Atrial Fibrillation

BACKGROUND: Abnormalities in the left atrial (LA) structure and function may develop in patients with paroxysmal atrial fibrillation (AF). We sought to determine the contribution of LA mechanical function, including LA stiffness, to AF by comparing patients with paroxysmal AF with normal control subjects, and to evaluate whether LA mechanical function and stiffness are related with the structural changes of LA. METHODS: Sixty-four paroxysmal AF patients (57 +/- 13 years, 59% male) were studied, using a speckle tracking echocardiography, and were compared with 34 age-, gender-, and left ventricular (LV) mass-matched controls (53 +/- 14 years, 61% male). LA volume indices, expansion index for reservoir function, active emptying fraction for contractile function, mitral annular velocities, and global longitudinal LA strain were measured. The ratio of E/e' to LA strain was used as an index of LA stiffness. RESULTS: Patients with paroxysmal AF had similar LV volume indices, ejection fraction, and diastolic function, when compared with that of the normal controls. However, paroxysmal AF patients showed increased LA volume indices and decreased LA reservoir function, but similar contractile function. LA stiffness was increased in patients with paroxysmal AF than in the control subjects (0.40 +/- 0.25 vs. 0.29 +/- 0.10, p = 0.002), and was related with LA volume indices and reservoir function. CONCLUSION: Patients with paroxysmal AF have decreased LA reservoir function and increased stiffness, in comparison with that of the control subjects. LA stiffness was significantly related with LA volume indices and reservoir function. LA stiffness can be used for the assessment of LA function in patients with paroxysmal AF.

Exercise Training Improves Age-Related Myocardial Metabolic Derangement: Proton Magnetic Resonance Spectroscopy Study in the Rat Model

BACKGROUND AND OBJECTIVES: The objective of this study was to determine whether long-term exercise training will improve age-related cardiac metabolic derangement using proton magnetic resonance (MR) spectroscopy. MATERIALS AND METHODS: Young and old male Fischer 344 rats were assigned to sedentary controls groups {young control (YC) group-3 months of age: YC, n=10; old control (OC) group-22 months of age: OC, n=10}, and an exercise training group (OT, n=5). After 12-week of treadmill exercise training, MR spectroscopy at 4.7 T was performed to assess myocardial energy metabolism: measurements of myocardial creatine-to-water ratio (Scr/Sw) were performed using the XWIN-NMR software. RESULTS: Exercise capacity was 14.7 minutes greater in OT than that in OC (20.1+/-1.9 minutes in OT, 5.4+/-2.3 minutes in OC; p0.05). The creatine-to-water ratios in the interventricular septa of YC did not differ significantly from that of OT (0.00131+/-0.00025 vs. 0.00127+/-0.00031; p=0.37). However, OC showed significant reduction in creatine-to-water ratio compared to OT (0.00096+/-0.00025 vs. 0.00127+/-0.00031; p<0.001). Mean total creatine concentrations in the myocardium were similar between YC and OT (13.3 +/-3.6 vs. 11.5+/-4.1 mmol/kg wet weight; p=0.29). In contrast, the mean total creatine concentration of OC was significantly reduced compared to OT (6.8+/-3.2 vs. 11.5+/-4.1 mmol/kg wet weight; p=0.03). CONCLUSION: Our findings suggest that long-term exercise training in old rats induced prevention of age-related deterioration in myocardial metabolism.