Decreased left ventricular stroke volume is associated with low-grade exercise tolerance in patients with chronic obstructive pulmonary disease.

BACKGROUND: Low-grade exercise tolerance is associated with a poor prognosis in patients with chronic obstructive pulmonary disease (COPD). The 6 min walk test (6MWT) is commonly used to evaluate exercise tolerance in patients with COPD. However, little is known regarding the relationship between cardiac function and exercise tolerance in patients with COPD. The aim of this study was to identify predictive factors in cardiac function for low-grade exercise tolerance in patients with stable COPD. METHODS: We recruited 57 patients with stable COPD (men 54, women 3) to perform the 6MWT. Patients with underlying orthopaedic disease or heart failure were excluded. Cardiac function was evaluated by echocardiography and contrast-enhanced cardiac CT. We also measured pulmonary function and the 6MWT distance. RESULTS: Forced expiratory volume in 1 s (FEV1) and per cent predicted FEV, along with left ventricular end diastolic volume and left ventricular cardiac output as measured by cardiac CT, were significantly related to the 6MWT distance. On multivariate analysis, left ventricular stroke volume was the factor most closely associated with a decreased walked distance in the 6MWT. CONCLUSIONS: Decreased left ventricular stroke volume was associated with low-grade exercise tolerance in patients with stable COPD without heart failure.

The association between defibrillation shock energy and acute cardiac damage in patients with implantable cardioverter defibrillators.

BACKGROUND: The aim of this study was to establish a minimally invasive defibrillation testing (DT) protocol for patients with implantable cardioverter defibrillators (ICDs). METHODS: Two different energy DTs were performed, immediately after (15 J-DT) and 7 days after (≤10 J-DT) device implantation, in 20 consecutive ICD implantation patients. Cardiac-troponin T (c-TNT) and heart-type fatty acid binding protein (H-FABP) levels were measured before implantation, 2 h after implantation, and 1 day after each DT. For an additional 122 patients with ICD, we retrospectively analyzed 203 DTs immediately and 7 days after device implantation. RESULTS: Serum c-TNT levels were significantly elevated 2 h after 15 J-DT [0.008 (0.004-0.019) vs. 0.053 (0.037-0.068) ng/mL, p<0.001], but not ≤10 J-DT [0.007 (0.004-0.018) ng/mL]. Similarly, serum H-FABP levels were significantly elevated 2 h after 15 J-DT (2.9±1.5 vs. 6.4±3.4 ng/mL, p<0.001), but not ≤10 J-DT (2.7±1.5 ng/mL). The changes in c-TNT and H-FABP levels between baseline and 2 h after DT were significantly greater for 15 J-DT compared with ≤10 J-DT [c-TnT: 0.039 (0.029-0.060) vs. 0 (0-0.003) ng/mL, p<0.001; H-FABP: 3.6±2.8 vs. -0.16±1.1 ng/mL, p<0.001]. The success rates of the initial shocks delivered for ventricular fibrillation were no different between ≤10 J-DT (85% [78/92]) and ≥15 J-DT (92% [103/111]). CONCLUSIONS: Elevated levels of myocardial damage markers such as c-TNT and H-FABP were not found after ≤10 J-DT. In addition, an acceptable success rate was confirmed in ≤10 J-DT.

Low arterial blood oxygenation is associated with calcification of the coronary arteries in patients with chronic obstructive pulmonary disease.

BACKGROUND: Cigarette smoking is a well-known major cause of both chronic obstructive pulmonary disease (COPD) and atherosclerosis. However, few studies have investigated the correlation between COPD and coronary atherosclerosis. METHODS: We recruited 54 patients with stable COPD (51 men, 3 women) but without angina symptoms. Arterial blood gas analyses were performed, pulmonary function was assessed, and calcification of the coronary arteries was evaluated by computed tomography (CT). RESULTS: Calcification of the coronary arteries was noted in 25 patients. There were no significant differences in age, body mass index, respiratory function, and levels of low-density lipoprotein cholesterol, hemoglobin A1c, glucose, or C-reactive protein between patients with or without calcification of the coronary arteries. Arterial blood oxygenation was significantly lower in patients with calcification of the coronary arteries. On both univariate and multivariate analyses, low arterial blood oxygenation was an independent risk factor for calcification of the coronary arteries. CONCLUSIONS: In patients with COPD, low arterial blood oxygenation was strongly associated with calcification of the coronary arteries and may be a significant predictor of cardiovascular disease.

Two-dimensional speckle tracking imaging as a novel strategy for accurately identifying the accessory pathway.

A 14-year-old patient was diagnosed with hypertrophic cardiomyopathy associated with Wolff-Parkinson-White syndrome. The two-dimensional speckle tracking strain method showed normal left ventricular local contraction, but the peak systolic longitudinal strain of the right ventricular (RV) anterior wall was earlier than that of the septal wall. As expected, the location of the accessory pathway was at the RV anterior wall. The patient's RV local contraction was normalized by successful radiofrequency application.

Role of epicardial adipose tissue in coronary artery disease in non-obese patients.

BACKGROUND: Epicardial adipose tissue (EAT) surrounding the heart may contribute to the development of coronary artery disease (CAD) through its local secretion of adipocytokines. Although the quantity of EAT is associated with obesity and metabolic syndrome, the role of EAT in the development of CAD in non-obese patients remains to be determined. METHODS: This study included 41 patients with CAD who underwent coronary artery bypass graft surgery and 28 patients without CAD who underwent other cardiac surgery. EAT volume was measured by 64-slice multi-detector computed tomography before the surgery. We obtained pericardial fluid and epicardial and subcutaneous adipose tissue samples at the surgery. We investigated the relationship between EAT volume and adiponectin levels in pericardial fluid and incident CAD in patients with and without obesity (body mass index>25 kg/m(2)). RESULTS: There was no significant difference in EAT volume between obese patients with and without CAD (55.5 ± 40.2 mL vs. 40.1 ± 19.7 mL, p=0.323). However, EAT volume was significantly greater in non-obese patients with CAD compared to those without CAD (35.0 ± 18.8 mL vs. 15.7 ± 11.0 mL, p<0.001). Adiponectin concentrations in pericardial fluid were significantly lower in non-obese patients with CAD compared to those without CAD (2.7 ± 2.0 µg/mL vs. 4.3 ± 3.7 µg/mL, p=0.049), whereas the adiponectin levels were decreased in obese patients regardless of the presence of CAD. Non-obese patients with CAD had significantly larger size adipocytes in EAT but not subcutaneous adipose tissue compared to those without CAD. Multiple logistic regression analysis showed that increased EAT volume was independently associated with incident CAD in non-obese patients. CONCLUSION: Increased EAT may play a crucial role in development of CAD through impairment of adiponectin secretion in non-obese patients.

Circulating heart-type fatty acid binding protein levels predict the occurrence of appropriate shocks and cardiac death in patients with implantable cardioverter-defibrillators.

BACKGROUND: The association between ongoing myocardial damage and outcomes in patients who have received an implantable cardioverter-defibrillator (ICD) is unclear. METHODS AND RESULTS: Consecutive patients with cardiomyopathy, who had received an ICD (n = 107, mean age 65 ± 11 years), were prospectively enrolled. Myocardial membrane injury (heart-type fatty acid binding protein [H-FABP] >4.3 ng/mL) and myofibrillar injury (troponin T >0.01 ng/mL) were defined using receiver operating characteristic curves. Patients were followed for a median of 33.6 months, to an end point of appropriate ICD shock or cardiac death. Myocardial membrane injury (45%) and myofibrillar injury (41%) were equally prevalent among patients with cardiomyopathy who had received ICDs. Appropriate ICD shocks or cardiac death occurred in 31% and 15% of patients, respectively. Multivariate Cox regression analysis showed that serum H-FABP levels >4.3 ng/mL, but not troponin T levels, were a significant independent prognostic factor for cardiac events (hazard ratio 5.502, 95% confidence interval 1.705-17.75, P = .004). Subgroup analysis revealed that measuring H-FABP levels was valuable for anticipating event-free survival among patients with ICDs who were receiving amiodarone. High H-FABP levels also predicted subsequent outcomes in patients who had received ICDs for primary or secondary prevention. CONCLUSION: Evaluating myocardial damage using H-FABP may be a promising tool for predicting outcomes in patients with cardiomyopathy who have received ICDs.

Device troubleshooting: cross connection of ventricular leads in a patient with decreased right ventricular electrical activity.

A patient with cardiac sarcoidosis showed low R-wave amplitude in the entire right ventricle (RV). To troubleshoot this, a left ventricular (LV) lead was implanted in the coronary vein. The pace/sense terminal of the defibrillation lead was connected to LV:IS-1 of the defibrillator. Conversely, the LV lead was connected to RV:IS-1. Induced ventricular fibrillation was successfully terminated without any undersensing.

Serum pregnancy-associated plasma protein a in patients with heart failure.

BACKGROUND: Pregnancy-associated plasma protein A (PAPP-A) proteolyzes insulin-like growth factor (IGF)-binding proteins and thus increases IGF-1 bioactivity. PAPP-A has been reported to be involved in various pathophysiologic abnormalities; however, the clinical significance of PAPP-A has not been examined in cases of heart failure (HF). We hypothesized that PAPP-A levels might be correlated with the severity of HF. METHODS AND RESULTS: PAPP-A and B-type natriuretic peptide (BNP) levels were measured in 262 subjects (182 HF patients and 80 control subjects). PAPP-A levels were higher in patients with HF than in control subjects and increased with advancing New York Heart Association functional class. There were 53 cardiac events during a mean follow-up period of 796 days. PAPP-A levels were higher in patients with cardiac events than in event-free patients. Patients were divided into 3 groups on the basis of their PAPP-A and BNP levels. Kaplan-Meier analysis demonstrated that the group with both high BNP with high PAPP-A had a significantly higher cardiac event rate than other groups. CONCLUSIONS: Serum PAPP-A levels were related to the severity of HF and associated with a high risk for adverse cardiac events in HF patients, suggesting that PAPP-A might be involved in the pathogenesis of HF.

Difference of clinical course after catheter ablation of atrioventricular nodal reentrant tachycardia between younger and older patients: atrial vulnerability predicts new onset of atrial fibrillation.

BACKGROUND: The aim of this study was to compare the long-term procedural outcomes, the stability of atrioventricular conduction, and the new onset of atrial fibrillation (AF), after ablation of atrioventricular nodal reentrant tachycardia (AVNRT). METHODS AND RESULTS: Consecutive patients with AVNRT (n=109), who underwent slow-pathway ablation, were divided into two groups based on the median age of the studied patients: the younger group aged <55 years and the older group aged ≥55 years. During a mean follow-up period of 60.6 months, the rate of change in the PR interval from before ablation to follow-up was significantly greater in older patients compared with younger patients. However, there was no delayed-onset high-degree AV block during follow-up in either group. No patients in the younger group suffered from persistent AF, whereas persistent AF occurred in 5/54 (9.3%) older patients. Multivariate Cox analysis revealed that atrial vulnerability, with induction of AF during the electrophysiological study, was the only predictor of the development of AF (Hazard ratio: 13.9, 95% confidence interval: 1.62-119.2, p<0.01). CONCLUSION: Slow-pathway ablation of AVNRT is a reliable strategy even in older patients. However, physicians should consider regular long-term follow-up of older patients with atrial vulnerability, in order to assess the subsequent development of AF.

Elevated cystatin C levels predict the incidence of vasospastic angina.

BACKGROUND: Cystatin C, a marker for early stage chronic kidney disease, has been shown to be involved in cardiovascular disease. The relationship between serum cystatin C levels and coronary vasospastic angina (VSA), however, remains to be elucidated. The aim of the present study was to investigate whether elevated cystatin C levels predict the incidence of VSA. METHODS AND RESULTS: One hundred and ten patients were referred to hospital due to suspected VSA. VSA was evoked in 59 patients by a vasospasm provocation test with administration of acetylcholine into the coronary arteries. The patients with VSA had lower levels of high-density lipoprotein cholesterol and a higher history of cigarette smoking, higher levels of triglyceride, high-sensitivity C-reactive protein, and higher cystatin C levels compared with those without VSA. There were no differences in serum creatinine or estimated glomerular filtration rate between patients with and without VSA. Multivariate logistic regression indicated that history of smoking (odds ratio, 2.956 P<0.05) and cystatin C levels (odds ratio, 2.285; P<0.01) were independently associated with the incidence of VSA. CONCLUSIONS: Elevated cystatin C levels were associated with higher incidence of VSA, suggesting that mild renal dysfunction may be implicated in the pathogenesis of coronary artery spasm.

Increased left atrial volume index predicts a poor prognosis in patients with heart failure.

BACKGROUND: Left atrial volume index (LAVI) is known to reflect the duration and severity of increased left atrial pressure caused by left ventricular (LV) diastolic dysfunction. However, the prognostic value of LAVI in patients with heart failure (HF) has not been fully investigated. METHODS AND RESULTS: Transthoracic echocardiography was performed in 146 consecutive patients (78 men, 68 women; mean age 72 ± 12 y) who were hospitalized for HF. There were 45 cardiac events (32%) during a median follow-up period of 448 days. There were no significant differences in LV end-diastolic dimensions or ejection fraction between patients who did or did not have cardiac events. However, LAVI was markedly higher in patients with, than those without, cardiac events (56 ± 26 vs 44 ± 22 mL/m(2); P < .01). Kaplan-Meier analysis showed that there was a stepwise increase in risk of cardiac events with each increment of LAVI category, and LAVI >53.3 mL/m(2) correlated with the highest risk of cardiac events (log-rank test; P < .01). Multivariate Cox proportional hazard analysis showed that high LAVI was an independent predictor for cardiac events (hazard ratio 1.427; 95% confidence interval 1.024-1.934; P < .05). CONCLUSION: LAVI may be useful for stratification of risk in patients with HF.

Suppressive effects of valsartan on microalbuminuria and CRP in patients with metabolic syndrome (Val-Mets).

The presence of metabolic syndrome (Mets) increases the risk for cardiovascular disease. There is a significant correlation between the levels of urinary albumin to creatinine ratio (UACR) and high-sensitive C-reactive peptide (hs-CRP), and accumulation of each Mets component. Increasing evidence has shown the importance of blockade of renin-angiotensin-systems (RAS) for reducing urinary albumin excretion and hs-CRP levels in Mets patients. However, the impact of RAS blockade on these effects in hypertensive (HT) Mets patients without diabetes mellitus (DM) has not been evaluated. We prospectively measured the levels of UACR and hs-CRP in 153 HT patients with and without Mets. Body weight; waist circumference; presence of dyslipidemia and DM, and levels of HOMA-R, UACR, and hs-CRP were significantly higher in HT patients with Mets than in those without Mets. After we treated these Mets patients with valsartan for 6 months, blood pressure (BP), UACR, and hs-CRP were decreased, whereas body weight, HOMR-R, and the lipid profile were not changed. In HT Mets patients without DM, 6 months after valsartan administration, levels of UACR and hs-CRP were also significantly decreased by 37.8% (-9.0-56.5%, p < 0.05) and 23.6% (-28.7-73.4%, p < 0.05), respectively. However, the percentage change of UACR and hs-CRP was not correlated with the reduction in BP. Valsartan administration lowered increased levels of chronic inflammation in both HT Mets patients with DM and in those without DM. These results indicate that the anti-inflammatory properties of valsartan might also have beneficial effects in Mets patients without DM.

Persistent abnormal value of late potential in Brugada syndrome associated with hypokalemia.

Hypokalemia accentuates the electrocardiographic (ECG) pattern of Brugada syndrome. We report two patients with Brugada syndrome and hypokalemia-induced lethal events. Despite concealing the typical ECG pattern with normalization of serum potassium levels, late potentials were persistently detected by signal-averaged ECG, even at the 18-month follow-up. An implantable cardioverter defibrillator was inserted to prevent sudden cardiac death.

8-Hydroxy-2'-deoxyguanosine is a prognostic mediator for cardiac event.

BACKGROUND: DNA in the nucleus is one of the major targets of reactive oxygen species (ROS), and oxidative DNA damage has been implicated in the pathogenesis of chronic heart failure. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) is produced from deoxyguanosine in DNA by ROS. The purpose of this present study was to examine the clinical significance of serum 8-OHdG levels in patients with heart failure. METHODS: We measured serum 8-OHdG levels in 230 patients with chronic heart failure and 42 control subjects without heart failure by sandwich enzyme-linked immunosorbent assay. Patients were prospectively followed during a median follow-up period of 472 days with the end points of cardiac death or progressive heart failure requiring re-hospitalization. RESULTS: Serum 8-OHdG concentrations were higher in patients with heart failure than in control subjects (P < 0·001) and increased with advancing New York Heart Association (NYHA) functional class (P < 0·001). Normal upper limit of 8-OHdG level was determined as mean ± 2SD value from 42 control subjects (0·40 ng mL(-1)). Abnormally high serum 8-OHdG levels (> 0·40 ng mL(-1)) were observed in 21·2%, 43·1%, 42·6% and 69·4% through NYHA I to IV (P < 0·001). A total of 66 cardiac events occurred during a follow-up period, and Kaplan-Meier survival curves demonstrated that cardiac event rate was markedly higher in patients with high 8-OHdG levels than in those with normal 8-OHdG levels (62·4% vs. 29·6%, P = 0·0007). CONCLUSIONS: Serum 8-OHdG levels provide important prognostic information for the risk stratification of patients with heart failure.

A case of acute heart failure due to abrupt rupture of aortic aneurysm into pulmonary artery.

Aorto-pulmonary fistula caused by ruptured aortic aneurysm is rare and sometimes difficult to diagnose, resulting in progression of heart failure. We report a case of acute heart failure due to abrupt rupture of aortic aneurysm into the pulmonary artery. Although it is difficult to make an early diagnosis of aorto-pulmonary shunt, multi-detector computed tomography (MDCT) clearly detected this extracardiac shunt. Emergent surgical repair of aorto-pulmonary fistula was successfully achieved. MDCT is a useful modality to make an accurate diagnosis of extracardiac shunt and to decide the operative procedure non-invasively.

Iodine-123-metaiodobenzylguanidine imaging can predict future cardiac events in heart failure patients with preserved ejection fraction.

OBJECTIVE: Iodine-123-metaiodobenzylguanidine ((123)I-MIBG) has been used to assess the function of the cardiac sympathetic nervous system in patients with chronic heart failure (HF). The usefulness of (123)I-MIBG imaging for evaluating patients with heart failure with preserved ejection fraction (HFPEF) has not been established. METHODS: We performed (123)I-MIBG scintigraphy and echocardiography and measured the plasma brain natriuretic peptide (BNP) levels of 117 consecutive HF patients (64 men, mean age 66 ± 14 years) with a left ventricular ejection fraction (LVEF) of ≥50% who were admitted to our hospital. Patients were divided into 2 groups according to the New York Heart Association (NYHA) functional class. RESULTS: The (123)I-MIBG delayed heart-to-mediastinum (H/M) ratio was significantly lower, and the washout rate (WR) was higher in patients with HFPEF with advanced NYHA functional class (NYHA functional class I and II vs. III: 1.90 ± 0.34 vs. 1.49 ± 0.32, p < 0.0001; 25.9 ± 13.4 vs. 46.9 ± 16.3%, p < 0.0001, respectively). On the other hand, the (123)I-MIBG WR was not correlated with LVEF and had a weak correlation with plasma BNP levels (R = 0.207, p = 0.0346). Moreover, patients with a high (123)I-MIBG WR showed a poor clinical outcome (p = 0.0033). CONCLUSIONS: (123)I-MIBG imaging provides independent prognostic information in patients with HFPEF.

Trends in coronary risk factors among patients with acute myocardial infarction over the last decade: the Yamagata AMI registry.

AIM: Recently, there has been an increase in the prevalence of coronary risk factors, such as diabetes and dyslipidemia, in Japan; however, it is unclear whether this has resulted in an increased incidence of acute myocardial infarction (AMI). We investigated the relationship between risk factors changes and AMI incidence in a Japanese population. METHODS: Trends in AMI incidence (per 100,000 person-years) were examined using data from the Yamagata AMI Registry from 1993 to 2007. We included 6,222 patients with a first-ever AMI (4175 men). The prevalence of coronary risk factors was investigated in three age groups of AMI patients (<65, 65-74, and ≥75 years) for the periods 1993-1997, 1998-2002, and 2003-2007. Coronary risk factors were further compared between recently registered AMI patients and 2,400 age-matched controls. RESULTS: The age-adjusted incidence of AMI increased significantly in men, but not in women. Younger men particularly showed a significant increase in the incidence of AMI. The prevalence of hypertension and diabetes increased in both genders; however, the prevalence of treatment for risk factors was significantly lower in men than women. Younger men showed significant increases in obesity and hypertriglyceridemia. Consequently, risk factors associated with the metabolic syndrome had accumulated among younger men. We revealed that hypertension, diabetes, hypercholesterolemia and current smoking were independent risk factors for AMI. CONCLUSIONS: The incidence rate for AMI increased significantly in men, especially younger men. Preventive care for risk factors associated with metabolic syndrome, in addition to conventional risk factors, may be required in younger men.

Catheter ablation of ventricular tachycardia induced by injection of acetylcholine in the right coronary artery.

We report the case of a patient who suffered from early morning nonsustained ventricular tachycardia. Clinical ventricular tachycardia without coronary spasm was reproducibly induced only by injection of acetylcholine in the right coronary artery. A good pace mapping site with 30 ms early ventricular activity was present in the right ventricular free wall. After radiofrequency ablation based on electroanatomical mapping, the tachycardia could no longer be induced by intracoronary injection of acetylcholine.

Low wall velocity of left atrial appendage measured by trans-thoracic echocardiography predicts thrombus formation caused by atrial appendage dysfunction.

BACKGROUND: Atrial fibrillation is associated with ischemic stroke because of thrombi that form within the left atrial appendage (LAA). The aim of this study was to develop a new parameter for LAA function that is easily performed using transthoracic echocardiography (TTE). METHODS: TTE and transesophageal echocardiography were performed in 106 patients with stroke. LAA wall motion velocity (TTE-LAWV) was measured using Doppler tissue imaging at the LAA tip. RESULTS: TTE-LAWV was significantly lower in patients with atrial fibrillation and LAA thrombus than in those with atrial fibrillation and no LAA thrombus and in sinus rhythm (7.5 +/- 1.9 vs 10.0 +/- 3.4 and 13.8 +/- 5.7 cm/s, respectively, P < .05). TTE-LAWV was significantly correlated with LAA emptying flow velocity (R = 0.462, P < .05). The multivariate logistic regression analysis showed that TTE-LAWV < 8.7 cm/s was an independent predictor of LAA thrombus formation (odds ratio, 9.473; 95% confidence interval, 1.172-76.55; P < .05). CONCLUSION: TTE-LAWV can noninvasively evaluate LAA dysfunction and assist in the detection of LAA thrombus.