Short physical performance battery vs. 6-minute walking test in hospitalized elderly patients with heart failure

Aims

Functional decline due to skeletal muscle abnormalities leads to poor outcomes in patients with acute heart failure (AHF). The 6-minute walking test (6MWT) reliably evaluates functional capacity, but its technical difficulty for the elderly often limits its benefits. Although the Short Physical Performance Battery (SPPB) is a comprehensive measure of physical performance, its role in AHF remains unclear. This study aimed to examine the prognostic significance of SPPB compared to the 6MWT in elderly patients hospitalized for AHF.

Methods and results

We retrospectively analysed 1192 elderly patients with AHF whose SPPB and 6MWT were measured during the hospitalization. The primary outcome measure was defined as a composite of all-cause death and heart failure readmission until 1 year after discharge. Patients with lower SPPB scores (0-6, n = 373) had significantly poorer outcomes than those with higher SPPB scores (7-12, n = 819) even after multivariable adjustment [adjusted hazard ratio (HR) 1.28, 95% confidence interval (CI) 1.01-1.61; P = 0.049], similar to those with shorter 6MWT (

Conclusions

Reduced functional capacity assessed by either the SPPB or 6MWT was associated with worse outcomes in hospitalized elderly patients with AHF. The incremental prognostic value over the conventional risk factors was higher in 6MWT than in SPPB.

Trial Registration

UMIN000023929.

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Key Words

• Elderly
• Frailty
• Functional capacity
• Physical function

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MESH Headings Collapse

Grants

• Novartis Pharma Research Grants and Japan Heart Foundation Research Grant

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Prognostic significance of 2019 Asian Working Group for Sarcopenia update on definition of sarcopenia

Background/Introduction

Sarcopenia plays a major role in the pathophysiology of frailty and is associated with worse outcome in the elderly population including patients with heart failure. A recent update of the most common definition of sarcopenia in Asia, Asian Working Group for Sarcopenia (AWGS2019), included significant changes in the diagnostic algorithm with newly dividing sarcopenia into severe and “non-severe” sarcopenia.

Purpose

The objective of this study was to evaluate the differences between AWGS2014 and AWGS2019 in patients with heart failure.

Methods

In the multicenter prospective FRAGILE-HF registry, which included elderly (≥65 years old) patients who were hospitalized with heart failure, we studied 865 patients (80±8 years old, 42% female). All-cause death in 1-year follow-up was tracked.

Results

Based on the original version of AWGS (AWGS2014), 183 patients (21%) were diagnosed with sarcopenia, which was associated with higher age, lower physical performance, less muscle mass, and greater heart failure risk (all p<0.001) as well as higher rate of all-cause death (HR 1.90, p=0.004 after adjustment by multivariable regression). Those patients with sarcopenia by AWGS2014 were reclassified mainly to severe sarcopenia (155, 84.7%) by AWGS2019, and 25 (13.7%) and 2 (1.1%) were classified into sarcopenia and non-sarcopenia. Meanwhile, 24 (3.5%) and 4 (0.6%) of patients without sarcopenia by AWGS2014 were reclassified into sarcopenia and severe sarcopenia, respectively. Although severe sarcopenia by AWGS2019 was associated with higher age, lower physical performance, less muscle mass, and greater heart failure risk (all p<0.001), patients with “non-severe” sarcopenia was rather younger (p<0.001) and had better physical performance (p=0.021) despite less muscle mass (p<0.001) than those without sarcopenia. Multivariate Cox analysis demonstrated severe sarcopenia by AWGS2019 was an independent prognostic factor (HR 1.77, p=0.014), but “non-severe” sarcopenia was not (HR 1.52, p=0.37). The prognosis of patients who were reclassified from non-sarcopenia to sarcopenia or severe sarcopenia were comparable to those remained non-sarcopenia. When added to other risk factors, the prognostic predictability of AWGS2019 was significantly lower than AWGS2014 (net reclassification improvement −0.26, p=0.025).

Conclusions

About a half of “non-severe” sarcopenia in AWGS2019 were patients without sarcopenia in AWGS2014. The prognosis of such patients who were newly diagnosed as sarcopenia was good, resulting in low overall prognostic predictability of AWGS2019. A further consideration for diagnostic algorithms of sarcopenia may be warranted in patients with heart failure.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Japan Heart Foundation

Negative impact of skeletal muscle impairment in older patients with heart failure with reduced versus preserved ejection fraction

Background/Introduction

Reduced functional capacity is an important phenotype of heart failure (HF), even though it may be considered multifactorial, especially in HF with preserved ejection fraction (HFpEF). Impairment in skeletal muscle may be one of extra-cardiac factors for reduced functional capacity and subsequent poor outcome.

Purpose

We sought to investigate the impact of the impairment in skeletal muscle, defined by the cut-offs proposed by the international consensus, on functional capacity and clinical outcome, in HF patients with preserved and reduced EF (HFrEF).

Methods

This is a multicenter prospective study including 1317 consecutive older (≥65 years) hospitalized patients with HF [HFpEF (ejection fraction ≥45%, n=675, 82±7 years, 46.4% male) and HFrEF (ejection fraction <45%, n=642, 78±8 years, 68.4% male)].

Results

HFrEF patients were more likely to have low skeletal muscle mass measured by bioelectrical impedance analysis (30.9% vs 22.1%, p=0.003) whereas less likely to have low muscle strength (handgrip strength; 62.9% vs 73.8%, p<0.001) than HFpEF, resulting in similar prevalence of sarcopenia between the two groups (21.6% vs 18.1%, p=0.19). In HFrEF, presence of sarcopenia was an independent predictor of reduced functional capacity assessed by a 6-minute walk distance (standardized beta=−0.093, p=0.039 in multivariate linear regression analysis) and 1-year mortality (adjusted hazard ratio (aHR) and 95% CI; 2.14 (1.22–3.70), p=0.009 in multivariate Cox-regression analysis). In patients with HFpEF, sarcopenia could predict mortality (aHR and 95% CI; 2.23 (1.23–3.91), p=0.009), though its association with reduced functional capacity was not significant after multivariate adjustment (standardized beta=−0.059, p=0.20). Kaplan-Meier survival curves in HFpEF and HFrEF are shown (Figure).

Conclusion(s)

In older patients with HF, sarcopenia was similarly contributed to mortality in HFpEF and HFrEF whereas its influence on functional capacity was pronounced in HFrEF.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Japan Heart Foundation Research Grant

Combined pre- and post-capillary pulmonary hypertension defined by new criteria is worse prognosis group in patients with heart failure

Background

The 6th World Symposium on Pulmonary Hypertension suggested major revision about definition of pulmonary hypertension (PH) as mean pulmonary artery pressure (mPAP) >20 mmHg. The definitions of two subsets of PH due to left heart disease (PH-LHD) also revised. The aim of this study was to investigate clinical characteristics and outcomes of subsets of PH-LHD defined by new criteria.

Methods

We analyzed 701 patients admitted for symptomatic heart failure (NYHA ≥2) and underwent right heart catheterization at compensated stage between 2007 and 2016. These patients were divided into 4 groups as follows: (i) Isolated post-capillary PH (Ipc-PH); mPAP >20 mmHg and pulmonary artery wedge pressure (PAWP) >15 mmHg and pulmonary vascular resistance (PVR) <3 WU, (ii) Combined pre- and post-capillary PH (Cpc-PH); mPAP >20 mmHg and PAWP >15 mmHg and PVR ≥3 WU, (iii) pre-capillary PH; mPAP >20 mmHg and PAWP ≤15 mmHg, (iv) no PH; mPAP ≤20 mmHg. Kaplan-Meier curves were applied to investigate whether each groups predict heart failure (HF) death or HF readmission.

Results

The study patients were divided into Ipc-PH (n=268), Cpc-PH (n=54), Pre-capillary PH (n=112), and no PH (n=267). Cpc-PH was significantly associated with HF death or HF readmission as compared to other groups (Figure).

Conclusions

Cpc-PH defined by new criteria was significantly associated with poor long-term clinical outcomes, which suggests new criteria of two subsets of PH-LHD could be strict risk stratification for symptomatic heart failure.

Figure1. Kaplan-Meier curves.

Funding Acknowledgement

Type of funding source: None

P5504Comparison of in-hospital clinical outcomes of acute myocardial infarction between nonagenarians and octogenarians: a propensity-score matched analysis

Background

Acute myocardial infarction (AMI) in the very elderly is associated with high morbidity and mortality. Because the majority of study population in clinical researches focusing on the very elderly with AMI were octogenarians, clinical evidences regarding AMI in nonagenarians are sparse. The aim of the present study was to compare in-hospital clinical outcomes of AMI between octogenarians and nonagenarians.

Methods

We included consecutive 415 very elderly (≥80 years) patients with AMI, and divided into the nonagenarian group (n=38) and the octogenarian group (n=377). Clinical characteristics and in-hospital outcomes were compared between the 2 groups. Furthermore, we used propensity-score matching to find the matched octogenarian group (n=38).

Results

Percutaneous coronary interventions (PCI) to the culprit of AMI were similarly performed between the nonagenarian (86.8%) and octogenarian (87.0%) groups The incidence of in-hospital death in the nonagenarian group (13.2%) was similar to that in the octogenarian group (14.6%) (P=0.811). The length of hospital stay was significantly shorter in the nonagenarian group (7.4±4.2 days) than that in the octogenarian group (15.4±19.4 days) (P<0.001). After using the propensity-score matching, the incidence of in-hospital death was less in the nonagenarian group (13.2%) than in the matched octogenarian group (21.1%) without reaching statistical significance (P=0.361). The length of hospitalization was significantly shorter in the nonagenarian group (7.4±4.2 days) than in the matched octogenarian group (17.8±37.0 days) (P=0.01).

Clinical outcomes Nonagenarian group (n=38) Octogenarian group (n=377) P value In-hospital death, n (%) 5 (13.2) 55 (14.6) 0.811 Length of hospital stay (days) 7.4±4.2 15.4±19.4 <0.001 Length of CCU stay (days) 3.3±2.5 4.7±5.1 0.109 LVEF (%) 48.2±9.2 50.8±13.7 0.152 Peak CPK (U/L) 1424.8±1580.8 1640.1±2394.4 0.912 CCU indicates Coronary care unit; LVEF, Left ventricular ejection fraction; CPK, Creatine kinase.

Flow-chart

Conclusions

The in-hospital mortality of nonagenarians with AMI was comparable to that of octogenarians with AMI. In-hospital outcomes in nonagenarians with AMI may be acceptable as long as acute medical management including PCI to the culprit of AMI is performed.

Acknowledgement/Funding

None

Waon Therapy for Managing Chronic Heart Failure - Results From a Multicenter Prospective Randomized WAON-CHF Study

BACKGROUND

Waon therapy improves heart failure (HF) symptoms, but further evidence in patients with advanced HF remains uncertain.

METHODS AND RESULTS

In 19 institutes, we prospectively enrolled hospitalized patients with advanced HF, who had plasma levels of B-type natriuretic peptide (BNP) >500 pg/ml on admission and BNP >300 pg/ml regardless of more than 1 week of medical therapy. Enrolled patients were randomized into Waon therapy or control groups. Waon therapy was performed once daily for 10 days with a far infrared-ray dry sauna maintained at 60℃ for 15 min, followed by bed rest for 30 min covered with a blanket. The primary endpoint was the ratio of BNP before and after treatment. In total, 76 Waon therapy and 73 control patients (mean age 66 years, men 61%, mean plasma BNP 777 pg/ml) were studied. The groups differed only in body mass index and the frequency of diabetes. The plasma BNP, NYHA classification, 6-min walk distance (6MWD), and cardiothoracic ratio significantly improved only in the Waon therapy group. Improvements in NYHA classification, 6MWD, and cardiothoracic ratio were significant in the Waon therapy group, although the change in plasma BNP did not reach statistical significance. No serious adverse events were observed in either group.

CONCLUSIONS

Waon therapy, a holistic soothing warmth therapy, showed clinical advantages in safety and efficacy among patients with advanced HF.

Heart Rate Control With If Inhibitor, Ivabradine, in Japanese Patients With Chronic Heart Failure - A Randomized, Double-Blind, Placebo-Controlled Phase II Study

BACKGROUND

Elevated heart rate (HR) is an independent risk factor for cardiovascular outcomes in various cardiac diseases, including heart failure (HF).

METHODS AND RESULTS

Randomized placebo-controlled study was conducted to evaluate the effects of ivabradine, an Ifinhibitor, on the resting HR in 126 Japanese symptomatic HF patients with left ventricular ejection fraction ≤35%, resting HR ≥75 beats/min in sinus rhythm, and stable, optimal background treatment. Patients were randomly allocated into 3 groups: placebo; starting dose of ivabradine 2.5 mg twice daily (BID; 2.5 mg group); 5 mg BID group. The dose was increased up to 7.5 mg BID according to dose-adjustment criteria. After the 6-week treatment, the reductions in resting HR were significant in both the 2.5-mg (16.6±8.1 beats/min) and 5-mg (16.4±9.6 beats/min) groups (P<0.0001 for both groups) compared with placebo (1.7±8.7 beats/min). The most frequent side effect of ivabradine was phosphenes, but all were mild. Treatment was discontinued in 1 patient due to HF in the 5 mg group.

CONCLUSIONS

Ivabradine starting at 2.5 or 5 mg BID effectively reduced resting HR in Japanese HF patients. Ivabradine at the starting dose of 2.5 mg BID could be safer than 5 mg BID. (Circ J 2016; 80: 668-676).

Abstract 706: HDL and ApoA-I Inhibit Palmitate-induced Lipid Raft Trafficking of TLR4 and Inflammatory Cytokines Expression in Adipocytes

Background: Adipose tissue inflammation induces inflammatory molecules production leading to insulin resistance and increased cardiovascular disease risk. Recently it has become apparent that innate immune system is activated by saturated fatty acids (SFAs) by a process involved in TLR4 signaling. HDL and apoA-I has anti-inflammatory effects, however the mechanisms are not well understood in adipocytes.

Aims: We examined to elucidate the effect of HDL and/or ApoA-I mediated cholesterol efflux on induction of inflammatory gene expression by palmitate in adipocytes via TLR4 dependent immune system.

Methods: 3T3-L1 adipocytes are exposure to 250uM palmitate for periods of up to 24 hours with or without HDL or Apo A-I. Antisense directed to ABCG-1 or ABCA-1 is added 24 hours prior to each reagent challenge. Cells were harvested and estimated for expression of Saa 3 gene using real-time PCR or detection of TLR4 in raft or non raft by western blotting. Lipid rafts were purified by ultracentrifugation on discontinuous sucrose gradient, and identified by the presence of caveolin-1.

Results: TLR4 was translocated into lipid raft from non raft within 15 minutes and dislocated by 60 minutes after palmitate exposure. Saa 3 gene expression was significantly up-regulated by 24 hours palmitate exposure in adipocytes. TLR4 translocation to raft and Saa 3 gene up- regulation induced by palmitate was significantly inhibited by pretreatment of HDL or Apo A-I for 6 hours. Antisense directed to ABCG-1 or SRB1 abrogated these inhibitory effects by HDL, but not ApoA-I whereas antisense to ABCA-1 did by Apo A-I but not HDL.

Conclusions: These findings suggest that TLR4 mediates palmitate-induced Saa 3 gene expression in adipocytes. A reduction in membrane cholesterol mediated by ABCG-1, SRB1 or ABCA-1 can account for the ability of HDL or ApoA-I to disrupt stimulation of inflammatory cytokines by palmitate

[Case with Emery-Dreifuss muscular dystrophy diagnosed forty-two years after onset and implanted with a cardiac resynchronization therapy defibrillator]

The patient was a 53-year-old male. He showed steppage gait at the age of 11 and equinus foot at 13. He walked unaided with shoe-insoles to support his heels. Atrial fibrillation and cardiac hypertrophy were found in his 30s, and ventricular tachycardia (VT) was observed at the age of 48. Electrophysiological studies were performed, but VT was not sustained, symptomatic, or showed signs of infra-Hisian block, and a pacemaker was not indicated. At 53, he was introduced to a neurologist because of tetraplegia after the first episode of syncope. A spinal MR showed ossification of posterior longitudinal ligament (OPLL) and central cervical cord injury. Furthermore, he presented not only contracture in his shoulder, elbow, and ankles but also atrophy in his scapulohumeral and gastrocnemius muscles. In accordance with a diagnosis of Emery-Dreifuss muscular dystrophy (EDMD), provocative testing of VT was carried out, and a cardiac resynchronization therapy defibrillator (CRT-D) was implanted. Later, a mutation analysis of the LMNA gene disclosed a known missense mutation of p.Arg377His, and we diagnosed him as EDMD2 (laminopathy). Contractures could be the clue to diagnose EDMD and indicate the need for pacemakers and defibrillators in patients with cardiac conduction disorders.

Aortopulmonary fistula caused by an infected thoracic aortic false aneurysm rupturing after endovascular stent placement

We report a case of 74-year-old man presenting with a rupture of a thoracic aortic false aneurysm after undergoing conventional total arch replacement for aortic arch aneurysm (62 mm) and endovascular stent placement for descending aortic aneurysm (70 mm). His chief complaints at the present admission were fever and sensation of dyspnea and we put him on a course of antibiotics for stent graft infection. However he died of massive hemoptysis. From a standpoint of autopsy findings, a thoracic aortic false aneurysm formed at the just proximal landing zone owing to type Ia endoleak, and simultaneously stent graft infection lead to make fistula formation between the false aneurysm and the lung. We examined ourselves that stent graft infection and aortopulmonary fistula caused by an infected thoracic aortic false aneurysm rupturing into the lung should be promptly treated such as complete removal of the stent and another revascularization in a reasonable period of time except if there are complications such as comorbid1ities or withholding of consent. We experienced and reported one rare case associated with a rupture of thoracic aortic false aneurysm caused by stent graft infection and the fistulization between the lung and the stent graft.

Long-term clinical follow-up after sirolimus-eluting stent versus bare metal stent implantation in patients with acute coronary syndrome

BACKGROUND AND OBJECTIVE

Drug-eluting stents have been shown to reduce the incidence of restenosis and target vessel revascularization (TVR) compared with bare metal stents (BMSs); however, the long-term efficacy of sirolimus-eluting stent (SES) implantation in patients with acute coronary syndrome (ACS) has not been well established. We have investigated the long-term clinical outcome of SES in patients with ACS.

METHODS

Consecutive 245 patients with ACS treated by primary stenting within 24 hours after onset were enrolled. There were 128 patients treated with SES and 117 patients were treated with BMS. We evaluated the incidence of major cardiac events (MACE; total death, nonfatal myocardial infarction, TVR) at 3 years, comparing with 8-month clinical outcome.

RESULTS

Eight-month clinical follow-up shows a significantly lower incidence of TVR in the SES group, 3.1% in the SES group versus 9.4% in the BMS group (P = 0.04). At 3-year clinical follow-up, there was no significant difference in the rate of TVR between the two groups, 8.4% versus 12.4% (P = 0.37). Cumulative incidence of total MACE was 9.2% in the SES group compared with 15.9% in the BMS group (P = 0.18). Only one case of stent thrombosis was observed in the SES (late thrombosis), while two cases of stent thrombosis occurred in the BMS group (late and very late thrombosis; P = 0.55).

CONCLUSION

SES implantation in patients with ACS is associated with favorable long-term clinical outcome with no excess of late stent thrombosis. Further long-term clinical follow-up will be warranted to confirm the safety and efficacy of SES.

Determinants of In-Hospital Death and Rupture in Patients With a Stanford B Aortic Dissection

BACKGROUND

In Stanford B acute aortic dissection (AAD), medical treatment is the choice of therapy in the acute phase, however, a portion of patients experience complications caused by serious clinical outcomes including aortic rupture and abdominal visceral ischemia. The objective of this study was to determine the predictors of in-hospital events in an Asian cohort of Stanford type B AAD.

METHODS AND RESULTS

Hospital records were queried to identify patients that met following criteria: (1) AAD presenting within 14 days of symptom onset; and (2) computed tomography (CT) confirmation of a dissected descending aorta not involving the ascending aorta. An in-hospital event was defined as death, rupture/impending rupture, or organ malperfusion. Patient characteristics, inflammatory markers, and CT findings were obtained from clinical case records and retrospectively analyzed. Two hundred and twenty patients with Stanford B AAD were identified. In-hospital events occurred in 15 patients (there were 8 deaths, and 5 patients need to undergo emergent surgery because of impending rupture or rupture, and 4 patients experienced organ malperfusion). In univariate logistic regression analysis, the non-thrombosed type (odds ratio (OR) 3.88, 95% confidence interval (CI) 1.20-12.61, p=0.02) and maximum aortic diameter measured by an initial CT (each having a 5 mm increment: OR 1.61, 95% CI 1.20-2.15, p=0.001) were significant predictors of in-hospital events. In multiple logistic regression analysis, the only significant predictor was maximum aortic diameter measured by an initial CT (each having a 5 mm increment: OR 1.41, 95% CI 1.04-1.92, p=0.03).

CONCLUSION

The results identified a large maximum aortic diameter as the independent predictor of in-hospital events in Stanford type B AAD. The non-thrombosed type might also help differentiate high-risk patients.

[Fungal endocarditis found at onset of lower limb acute aortic occlusion; report of a case]

Fungal endocarditis caused by Candida species is associated with high morbidity and mortality. A combination of surgical resection and antifungal drug therapy is the golden standard for treatment. We reported a case of fungal endocarditis due to Candida lusitaniae found at onset of lower limb acute aortic occlusion cured by emergency operation. This case suggests that Candida endocariditis can be managed medically with antifungal drug therapy in life time.

Improvement of Cheyne-Stokes Respiration, Central Sleep Apnea and Congestive Heart Failure by Noninvasive Bilevel Positive Pressure and Medical Treatment

A 57-year-old man was admitted with dyspnea. Clinical evaluation revealed atrial fibrillation and congestive heart failure (CHF). Standard medical therapy of CHF failed to completely improve the dyspnea and polysomnography revealed Cheyne-Stokes respiration with central sleep apnea (CSR-CSA). He was equipped with noninvasive positive pressure ventilation (NPPV) with bilevel positive airway pressure (BiPAP). The combined therapy of medical treatment of the CHF and administration of NPPV with BiPAP reduced the CSR-CSA. This regimen resulted in marked improvement of cardiac function, evaluated by echocardiography, and reduction of plasma concentration of brain natriuretic peptide. After the patient recovered from CHF and was discharged from hospital, he continued to use NPPV with BiPAP at home. In patients with CHF, it is important to be aware of sleep-related breathing disorders because treatment will not only improve the hypoxemia, but also the cardiac dysfunction.

Sarcomatoid collecting duct carcinoma arising in the hemodialysis-associated acquired cystic kidney: an autopsy report

A case of sarcomatoid collecting duct carcinoma (CDC) arising in a long-term hemodialysis-associated acquired cystic kidney was reported. A 71-year-old woman with a 21-year history of hemodialysis showed a peritoneal metastatic carcinoma (carcinomatous peritonitis) with an unknown primary site. An autopsy revealed a sarcomatoid collecting duct carcinoma of the right kidney with multicyst formation. In addition to the carcinomatous peritonitis, the tumor metastasized to the lymph nodes and bilateral lung. The primary tumor was composed of both carcinomatous and sarcomatous components, suggesting a high-grade transformation. Carcinomatous tumor cells were positive for epithelial membranous antigen (EMA), cytokeratin, and reactive to soybean agglutinin and peanut agglutinin, whereas the sarcomatous cells were positive for vimentin as well as EMA. Thus, the immunohistochemical and lectin-histochemical analysis confirmed that the tumor originated in the medullary collecting duct. Although CDC is not common in acquired cystic kidney disease patients, attention should be given to the occurrence of high-grade carcinoma of rare histological variant, as well as conventional renal cell carcinoma.

Inhibition of carnitine synthesis modulates protein contents of the cardiac sarcoplasmic reticulum Ca2+-ATPase and hexokinase type I in rat hearts with myocardial infarction

It was previously reported that inhibition of carnitine synthesis by 3-(2,2,2-trimethyl-hydrazinium) propionate (MET-88) restores left ventricular (LV) systolic and diastolic function in rats with myocardial infarction (MI). Preservation of the calcium uptake function of sarcoplasmic reticulum Ca2+-ATPase (SERCA2) is one of the possible mechanisms by which MET-88 alleviates hemodynamic dysfunction. To test this hypothesis, the effects of MET-88 on protein content of SERCA2 were evaluated using the same rat model of heart failure. Myocardial protein content of hexokinase, which is one of the key enzymes of glucose utilization, was also measured. Either MET-88 (MET-88 group) or a placebo (MI group) was administered for 20 days to rats with MI induced by coronary artery ligation. The control group underwent sham surgery (no ligation) and received placebo. In LV myocardial homogenates, the myocardial SERCA2 protein content was 32% lower (p<0.05) in the MI group than in the control group. However, in the MET-88 group myocardial SERCA2 content was the same as in the control group. Hexokinase I protein content was 29 % lower (p<0.05) in the MI group compared with the control. In contrast, hexokinase II protein content did not differ significantly among the three groups. Consequently, inhibition of carnitine synthesis ameliorates depression of SERCA2 and hexokinase I protein content which may reduce tissue damage caused by MI.

End-tidal CO2 pressure decreases during exercise in cardiac patients: association with severity of heart failure and cardiac output reserve

OBJECTIVES

We measured end-tidal CO2 pressure (PETCO2) during exercise and investigated the relationship between PETCO2 and exercise capacity, ventilatory parameters and cardiac output to determine the mechanism(s) of changes in this parameter.

BACKGROUND

It is unclear whether PETCO2 is abnormal at rest and during exercise in cardiac patients.

METHODS

Cardiac patients (n = 112) and normal individuals (n = 29) performed exercise tests with breath-by-breath gas analysis, and measurement of cardiac output and arterial blood gases.

RESULTS

PETCO2 was lower in patients than in normal subjects at rest and decreased as the New York Heart Association class increased, whereas the partial pressure of arterial CO2 did not differ among groups. Although PETCO2 increased during exercise in patients, it remained lower than in normal subjects. PETCO2 in relation to cardiac output was similar in patients and normal subjects. PETCO2 at the respiratory compensation point was positively correlated with the O2 uptake (r = 0.583, p < 0.0001) and the cardiac index at peak exercise (r = 0.582, p < 0.0001), and was negatively correlated with the ratio of physiological dead space to the tidal volume. The sensitivity and specificity of PETCO2 to predict an inadequate cardiac output were 76.6% and 75%, respectively, when PETCO2 at respiratory compensation point and a cardiac index at peak exercise that were less than the respective control mean-2 SD values were considered to be abnormal.

CONCLUSIONS

PETCO2 was below normal in cardiac patients at rest and during exercise. PETCO2 was correlated with exercise capacity and cardiac output during exercise, and the sensitivity and specificity of PETCO2 regarding decreased cardiac output were good. PETCO2 may be a new ventilatory abnormality marker that reflects impaired cardiac output response to exercise in cardiac patients diagnosed with heart failure.

Detection of exogenous growth hormone (GH) administration by monitoring ratio of 20kDa- and 22kDa-GH in serum and urine

We previously demonstrated that individual subjects have fairly constant ratios of serum concentrations of 20 kDa- (20K) and 22 kDa-GH (22K). The aim of this study is to demonstrate the possibility of utilizing the changes in the ratio of 20K/22K for detecting the exogenous administration of 22K. A male patient with idiopathic dilated cardiomyopathy (age 51) received 22K (4U, s.c.) every other day. The concentrations of 20K and 22K in serum and urine were measured using enzyme-linked immunosorbent assays before and after administration. The administration of 22K increased total GH concentration, and markedly decreased the ratio of 20K/22K in serum, especially 2-10 h after the administration. From calculations, it became clear that the concentration of exogenous 22K reached a peak between 2-4 h after the administration and decreased to a negligible level after 24 h. The ratio of 20K/22K in the 0-24 h urine was 5 times lower than that in the 24-48 h urine. These data suggest that, by monitoring the ratio of 20K/22K in serum or urine, it is possible to determine whether or not GH has been externally administered and to calculate the serum GH that has been administered.

[Idiopathic cardiomyopathy: pathophysiology and hemodynamics]

Idiopathic cardiomyopathy is classified into three categories, namely, hypertrophic, dilated and restrictive cardiomyopathy. Pathophysiology and hemodynamics are quite different between the three types of cardiomyopathies. Hypertrophic cardiomyopathy is hemodynamically characterized by outflow obstruction and diastolic dysfunction. In dilated cardiomyopathy, progressive dilatation and systolic dysfunction of the left ventricle are predominant. This left ventricular remodeling is strongly associated with neurohormonal activation occurred in this disease. In restrictive cardiomyopathy, left ventricular distensibility is markedly impaired and differential diagnosis from constrictive pericarditis is often difficult.

Analysis of nitric oxide in the exhaled air of patients with chronic glomerulonephritis

BACKGROUND

Nitric oxide (NO) plays an important role in renal hemodynamics and function. Although production of NO in the glomeruli has been found to be increased in animal models of glomerulonephritis, it remains unclear whether its endogenous production is enhanced in patients with chronic glomerulonephritis (CGN).

SUBJECTS AND METHODS

We measured NO output in exhaled air as an indicator of its local production in the lungs and plasma and urinary nitrite plus nitrate (NO2-/NO3-) levels as indicators of its production in the whole body in 21 patients with CGN in 31 healthy controls.

RESULTS

The patients exhaled higher concentrations of NO (29.5 +/- 1.4 vs. 18.7 +/- 1.0 parts per billion (ppb), mean +/- SEM, p < 0.0001) and exhaled NO output was also higher than in controls (166.6 +/- 6.8 vs. 95.5 +/- 5.6 nl/min/m2, p < 0.0001). Plasma NO2-/NO3- concentrations were also significantly greater in the patients than in the controls (81.6 +/- 7.2 vs. 41.1 +/- 4.3 micromol/l, p < 0.001). In patients with CGN, exhaled NO output correlated negatively with creatinine clearance (r = -0.62, p < 0.05). Oral administration of prednisolone (60 mg/day) for two weeks did not significantly affect the exhaled NO output in the patients (160 +/- 7 vs. 200 +/- 30 nl/min/m2, p = NS) despite a decrease in urinary protein excretion (12.0 +/- 2.9 vs. 1.4 +/- 0.6 g/day, p < 0.01).

CONCLUSION

These findings suggested that endogenous NO production is increased in patients with CGN. Increased endogenous NO production may play some pathophysiological role in these patients.

Improvement of impaired myocardial vasodilatation due to diffuse coronary atherosclerosis in hypercholesterolemics after lipid-lowering therapy

BACKGROUND

Diminished myocardial vasodilatation (MVD) in hypercholesterolemics without overt coronary stenosis has been reported. However, whether the diminished MVD of angiographically normal coronary arteries in hypercholesterolemics can be reversed after lipid-lowering therapy is not known.

METHODS AND RESULTS

A total of 27 hypercholesterolemics and 16 age-matched controls were studied. All patients had >1 normal coronary artery, and those segments that were perfused by anatomically normal coronary arteries were studied. Myocardial blood flow (MBF) was measured during dipyridamole loading and at baseline using positron emission tomography and 13N-ammonia, after which MVD was calculated before and after lipid-lowering therapy. Total cholesterol was significantly higher in hypercholesterolemics (263+/-33.8) than in controls (195+/-16.6), and it normalized after lipid-lowering therapy (197+/-19.9). Baseline MBF (ml. min-1. 100 g-1) was comparable among hypercholesterolemics (both before and after therapy) and controls. MBF during dipyridamole loading was significantly lower in hypercholesterolemics before therapy (189+/-75.4) than in controls (299+/-162, P<0.01). However, MBF during dipyridamole loading significantly increased after therapy (226+/-84.7; P<0.01). MVD significantly improved after therapy in hypercholesterolemics (2.77+/-1.35 after treatment [P<0.05] versus 2. 02+/-0.68 before treatment [P<0.01]), but it remained significantly higher in controls (3.69+/-1.13, P<0.01). There was a significant relationship between the percent change of total cholesterol and the percent change of MVD before and after lipid-lowering therapy (r=-0. 61, P<0.05).

CONCLUSIONS

Diminished MVD of anatomically normal coronary arteries in hypercholesterolemics can be reversed after lipid-lowering therapy.

Insulin action on heart and skeletal muscle FDG uptake in patients with hypertriglyceridemia

Abnormal heart and skeletal muscle 18F-fluorodeoxyglucose (FDG) uptake in patients with insulin resistance has been demonstrated. Although the existence of whole-body insulin resistance has been reported in hypertriglyceridemics, its specific role in heart and skeletal muscle FDG uptake in hypertriglyceridemics has not been clarified.

METHODS

We compared heart and skeletal muscle FDG uptake using PET and the whole-body glucose disposal rate (GDR) during insulin clamping in 17 hypertriglyceridemics and 12 age-matched control subjects to increase our knowledge of whole-body insulin resistance and its relationship to heart and skeletal muscle FDG uptake in hypertriglyceridemics.

RESULTS

GDR was significantly reduced in hypertriglyceridemics compared with control subjects (4.50 +/- 1.37 mg/min/kg versus 10.0 +/- 2.97 mg/min/kg, P = 0.00001), as were the skeletal muscle FDG Ki = (k1 x k3)/(k2 + k3) (SFKi: 0.007 +/- 0.003 mL/min/g versus 0.018 +/- 0.01 mL/min/g, P = 0.0001) and skeletal muscle FDG uptake ([SMFU] 0.725 +/- 0.282 mg/min/100 g versus 1.86 +/- 1.06 mg/min/100 g, P = 0.00023). However, myocardial FDG Ki (MFKi) tended to be reduced in hypertriglyceridemics compared with that in control subjects (0.062 +/- 0.017 mL/min/g versus 0.068 +/- 0.015 mL/min/g), but the difference was statistically insignificant (P = 0.3532). Moreover, myocardial FDG uptake (MFU) in hypertriglyceridemics (6.47 +/- 1.72 mg/min/100 g) tended to be reduced compared with that in control subjects (6.97 +/- 1.73 mg/min/100 g), but the difference was statistically insignificant (P = 0.4485). GDR was significantly correlated with SFKi (r = 0.69, P = 0.0022), SMFU (r = 0.612, P = 0.009), MFKi (r = 0.57, P = 0.0174) and MFU (r = 0.505, P = 0.0385) in hypertriglyceridemics.

CONCLUSION

Both heart and skeletal muscle glucose utilization were related to insulin resistance in hypertriglyceridemics. However, the less severe reduction in MFU (compared with SMFU) suggests that myocardium may have a mechanism to oppose insulin resistance in hypertriglyceridemics.

Kinetics of oxygen uptake at onset of exercise related to cardiac output, but not to arteriovenous oxygen difference in patients with chronic heart failure

Patients with chronic heart failure performed exercise tests to evaluate the relation of kinetics of oxygen uptake to cardiac output and arteriovenous oxygen difference at the onset of exercise. The kinetics of oxygen uptake are primarily determined by cardiac output; these kinetics are useful in evaluating exercise intolerance and cardiac output response during exercise.

The sarcoplasmic reticulum Ca2+-ATPase (SERCA2) gene promoter activity is decreased in response to severe left ventricular pressure-overload hypertrophy in rat hearts

The sarcoplasmic reticulum Ca2+-ATPase (SERCA2) pump plays a key role in the contraction-relaxation cycle of the myocardium by controlling the intracellular Ca2+ concentration. SERCA2 protein and mRNA expression levels, as well as, SR Ca2+ uptake function are depressed in hypertrophied and failing myocardium. At this time, the molecular mechanisms regulating SERCA2 gene transcription during hypertrophy and heart failure are not completely understood, especially in vivo. Direct gene transfer into adult cardiac tissue has recently been shown to be a useful technique to study in vivo gene regulation. In this study, SERCA2 promoter-luciferase (Luc) reporter constructs of various lengths were injected into the beating left ventricular apex of adult rats (groups = compensated hypertrophy, heart failure, and controls) and the expression level was analysed. Our SERCA2 promoter analyses revealed three positive regulatory regions between -1810 bp and -1110 bp, -658 bp and -284 bp, and -267 bp and -72 bp and a negative regulatory region between -1110 bp and -658 bp, important for in vivo expression in rat hearts. SERCA2 promoter activity was also assessed in rat hearts with compensated pressure-overload hypertrophy (induced by the DOCA-salt treatment) and heart failure (induced by severe ascending aortic constriction). In the DOCA-salt-induced hypertrophy model, SERCA2 promoter activity was similar to that of sham controls. In contrast, severe constriction of the ascending aorta decreased the expression of the -1810 Luc and -1110 Luc constructs by 92.8% and 64.3%, respectively. This study suggests that only severe pressure-overload hypertrophy produces a significant decrease in SERCA2 promoter activity, and the promoter region extending to -1810 bp is sufficient for the down regulation of SERCA2 gene expression.

Functional characterization of Dictyostelium discoideum mutant myosins equivalent to human familial hypertrophic cardiomyopathy

Familial hypertrophic cardiomyopathy (FHC) is caused by missence mutations in beta-myosin heavy chain or other various sarcomeric proteins. To elucidate the functional impact of FHC mutations in myosin heavy chain, we generated Dictyostelium discoideum myosin II mutants equivalent to human FHC mutations by site-directed mutagenesis, and characterized their molecular-basis motor function. The current mutants, i.e. R397Q, F506C, G575R, A699R, K703Q and K703W are equivalent to R403Q, F513C, G584R, G716R, R719Q and R719W FHC mutants respectively. We measured the molecular-basis force and the sliding velocity generated by these myosin mutants. The measurement revealed that the A699R, K703Q and K703W myosins exhibited the lowest level of force with their preserved actin-activated MgATPase activity. F506C mutant showed the least impairment of the motile and enzymatic activities. The motor function of R397Q and G575R myosins were classified as intermediate. These results suggest that ELC binding domain might be important for force production.

Distinct kinetic properties of cardiac myosin isoforms revealed by in vitro studies

To clarify the physiological significance of myosin isoform redistribution in cardiac adaptation process, we compared the kinetic property of the two cardiac myosin isoforms using in vitro motility assay techniques. Cardiac myosin isoforms V1 and V3 were obtained from ventricular muscle of young rats and hypothyroid rats respectively. On each of these myosin isoforms fixed on a glass coverslip, fluorescently labeled actin filaments were made to slide in the presence of ATP. To measure the force generated by actomyosin interaction, a small latex bead was attached to the barbed end of an actin filament and the bead was captured by the laser optical trap installed in a microscope. The force was determined from the distance between the bead and the trap positions under either auxotonic or isometric conditions. The time-averaged force generated by multiple cross-bridges did not differ significantly between the two isoforms. On the other hand, the unitary force measurement revealed the same level of amplitude but a longer duration for V3 isoform. The same level of time-averaged force is in agreement with not only our previous finding but the results of maximum force measurement in muscle preparations. The difference in kinetic characteristics of the two isoforms could account for the difference in economy of force development and the basis for cardiac adaptation mechanism.

Effect of inhaled nitric oxide on gas exchange in patients with congestive heart failure. A randomized, controlled trial

BACKGROUND

Conventional vasodilators increase ventilation-perfusion mismatch and do not improve gas exchange even though they reduce pulmonary hypertension. However, the effects of nitric oxide inhalation on ventilatory and gas exchange values in patients with congestive heart failure are not known.

OBJECTIVE

To investigate the effect of nitric oxide inhalation on gas exchange in patients with congestive heart failure.

DESIGN

Randomized, controlled trial.

SETTING

University hospital.

PATIENTS

16 patients with congestive heart failure (New York Heart Association class II or III).

INTERVENTIONS

Patients inhaled nitric oxide gas at graded concentrations (n = 8) or were given intravenous isosorbide dinitrate, 2.5 mg (n = 8).

MEASUREMENTS

Hemodynamic and ventilatory variables and blood gases were measured 5 minutes after inhalation of different doses of nitric oxide and 10 minutes after administration of isosorbide dinitrate.

RESULTS

Nitric oxide inhalation reduced the mean pulmonary arterial pressure in a dose-dependent manner without altering the mean arterial pressure or cardiac output. At a dose of 40 parts per million, nitric oxide inhalation increased PaO2 (change from baseline, 12.0 mm Hg [95% CI, 2.3 to 21.7 mm Hg]; P = 0.014) and decreased the alveolar-arterial difference in partial pressure of oxygen (change, -8.6 mm Hg [CI, -16.8 to -0.4 mm Hg]; P = 0.038) and the ventilatory equivalent for carbon dioxide output (change, -6.7 [CI, -10.3 to -3.1]; P < 0.001). Although isosorbide dinitrate similarly decreased pulmonary arterial pressure, it did not alter gas exchange or ventilatory variables.

CONCLUSIONS

Because nitric oxide inhalation improved gas exchange, it may be used as a supportive therapy when other conventional vasodilators worsen gas exchange.