Improvement in Vascular Endothelial Function following Transcatheter Aortic Valve Implantation.

Background and objectives: Endothelial dysfunction is associated with exercise intolerance and adverse cardiovascular events. Transcatheter aortic valve implantation (TAVI) is applied to treat elderly patients with severe aortic stenosis, but less is known about the impact of TAVI on endothelial dysfunction, which can be assessed by measuring flow-mediated vasodilation (FMD). In this parameter, a low value indicates impaired endothelial function. Materials and Methods: Vascular endothelial function was evaluated by FMD of the brachial artery just before and one week after TAVI. Factors associated with the normalization of FMD and their prognostic impact were investigated. Results: Fifty-one patients who underwent TAVI procedure (median 86 years old, 12 men) were included. FMD improved significantly from baseline to one week following TAVI (from 5.3% [3.7%, 6.7%] to 6.3% [4.7%, 8.1%], p < 0.001). Among 33 patients with baseline low FMD (≤6.0%), FMD normalized up to >6.0% following TAVI in 15 patients. Baseline higher cardiac index was independently associated with normalization of FMD following TAVI (odds ratio 11.8, 95% confidence interval 1.12-124; p < 0.04). Conclusions: Endothelial dysfunction improved following TAVI in many patients with severe aortic stenosis. The implication of this finding is the next concern.

High Cardiac Troponin I Is Associated With Transesophageal Echocardiographic Risk of Thromboembolism and Ischemic Stroke Events in Non-Valvular Atrial Fibrillation Patients.

BACKGROUND: Abnormalities in the left atrium (LA) detected on transesophageal echocardiography (TEE) are reliable predictors of thromboembolism in patients with atrial fibrillation (AF). Cardiac troponin I, a marker of subclinical myocardial damage, may also be a predictor of thromboembolic events in patients with AF. The relationship between cardiac troponin I and thromboembolic risk on TEE, however, remains unclear.Methods and Results:TEE and laboratory data, including high sensitivity cardiac troponin I (hs-cTnI) and CHA2DS2-VASc score, were analyzed in 199 patients with non-valvular AF (NVAF). Patients were stratified into those with or without LA abnormality, defined as LA appendage flow velocity <20 cm/s or dense spontaneous echo contrast. On multiple logistic analysis of the clinical variables, hs-cTnI was associated with LA abnormality (95% CI: 1.0003-1.020, P=0.034). The area under the curve for LA abnormality increased on addition of hs-cTnI to CHA2DS2-VASc score. The incidence rate of ischemic stroke was higher in the high hs-cTnI group than in the low-hs-cTnI group (log-rank test, P<0.05). CONCLUSIONS: Elevated hs-cTnI was independently associated with LA abnormality in NVAF patients. hs-cTnI level may be a useful biomarker for risk stratification of thromboembolism in NVAF patients.

Restrictive Lung Function Is Related to Sympathetic Hyperactivity in Patients With Heart Failure.

BACKGROUND: Sympathoexcitation and impaired lung function are common in patients with severe heart failure (HF). However, the association between impaired lung function and sympathoexcitation remains unknown. METHODS AND RESULTS: Muscle sympathetic nerve activity (MSNA) and clinical variables were determined in 83 HF patients with left ventricular ejection fraction (LVEF) <0.45. Restrictive and obstructive changes on spirometry were defined as reduced forced vital capacity (FVC) of <80% of predicted and a ratio of forced expiratory volume in the first second to FVC of <70%, respectively. Restrictive and obstructive changes were identified in 17 and 21 patients, respectively. MSNA was higher in patients with restrictive changes than in those without restrictive changes (84 vs 66 bursts per 100 beats; P < .01), but was similar in those with and without obstructive changes. Univariate analyses showed that FVC, estimated glomerular filtration rate (eGFR), specific activity scale, B-type natriuretic peptide level, LVEF, age, and use of aldosterone receptor blockers were significant predictors of MSNA burst incidence. Multivariate analysis revealed that FVC, LVEF, and eGFR were independent factors for increased burst incidence. Changes in FVC during follow-up negatively correlated with changes in burst rate (n = 11; P < .01). CONCLUSION: Restrictive lung function was associated with increased sympathetic nerve activity independently from HF severity.

Successful Withdrawal from Dobutamine by Canagliflozin in a Diabetic Patient with Stage D Heart Failure.

Patients with stage D heart failure (HF) frequently become dependent on high doses of diuretics and inotropic agents. Recently, a sodium-glucose cotransporter 2 inhibitor (SGLT2i), an oral antidiabetic agent, has been demonstrated to have favorable effects in preventing HF. However, it remains unknown whether SGLT2i is reliable for patients with decompensated HF. We experienced a case of a patient with stage D HF for whom attempting intravenous dobutamine withdrawal was difficult even after the administration of all conventional pharmacological treatment. Administration of canagliflozin produced an additive diuretic action and correction of volume overload in combination with azosemide and tolvaptan, and resulted in successful withdrawal of dobutamine. Thus, SGLT2i might be promising for the treatment of patients with congestive HF who are refractory to conventional diuretic treatment.

Sympathetic Nerve Activity Efferent Drive and Beta-Blocker Treatment　- Effect of Interaction in Systolic Heart Failure.

BACKGROUND: Although both ß-blocker dose (BBD) and sympathetic activity efferent drive are associated with prognosis in chronic heart failure (HF), little is known about the prognostic value of the interaction between them. METHODS AND RESULTS: Potential prognostic variables including resting muscle sympathetic nerve activity (MSNA) were investigated in 133 patients with HF (ejection fraction [EF] <0.45). BBD was normalized to therapeutically equivalent doses of carvedilol. Primary cardiovascular endpoints included cardiovascular death and HF hospitalization. Predictors for outcomes were assessed on univariate, multivariate, and Kaplan-Meier analysis. EF was followed for 9 months after MSNA measurement in 102 patients. During the 1,419±824-day follow-up period, 24 patients died (sudden death, n=10; progressive HF, n=14). On multivariate Cox proportional hazard analysis, higher MSNA (P=0.037; HR, 2.01) and lower BBD (<5.0 mg/day; P=0.041; HR, 1.94) were independent predictors of cardiovascular events. Patients were divided into higher MSNA (≥64 bursts/100 beats) and lower MSNA groups. Although lower BBD remained an independent predictor in patients with higher MSNA, BBD was not statistically significant in patients with lower MSNA on univariate analysis. Additionally, there was a lower EF change in patients with lower BBD and higher MSNA. CONCLUSIONS: Higher BBD might be necessary to avoid cardiovascular events in HF patients with central sympathetic overactivation. (Circ J 2016; 80: 2149-2154).

Transcatheter aortic valve implantation in an elderly man with severe aortic stenosis and high surgical risk.

An 85-year-old man with severe aortic stenosis (transaortic peak velocity 4.4 m/s, mean gradient 46 mmHg and valve area 0.71 cm(2)) was admitted to our hospital due to mild exertional dyspnea (NYHA class II). He had received low-dose prednisolone (5 mg/day) plus tacrolimus hydrate (1.5 mg/day) for rheumatic arthritis and interstitial pneumonia. Although aortic valve replacement was indicated, he was considered at high risk to undergo open heart surgery because of reduced pulmonary function (FEV1.0%, 77.2%) and long-term treatment with immunosuppressive drugs. After a multidisciplinary heart team conference, the decision was made to perform transfemoral transcatheter aortic valve implantation (TAVI) using a SAPIEN XT 26 mm valve. TAVI was completed in 105 minutes without any complications. After the procedure, his symptom was improved and his activity of daily life was maintained, and he was ambulatory the next day. Aortic stenosis by degenerative calcification is becoming increasingly common as the Japanese population ages. TAVI has been used to treat patients with concomitant diseases and at high risk of open heart surgery. We herein report a case with rheumatic arthritis and interstitial pneumonia that underwent successful TAVI.

Hyperuricemia and transesophageal echocardiographic thromboembolic risk in patients with atrial fibrillation at clinically low-intermediate risk.

BACKGROUND: There is no clear consensus on thromboprophylaxis in patients with nonvalvular atrial fibrillation (AF) at low-intermediate thromboembolic risk. Although hyperuricemia is a risk factor for cardiovascular diseases, the relationship between serum uric acid (UA) levels and thromboembolic risk has not been fully elucidated in patients with AF. METHODS AND RESULTS: Serum UA levels and the score for congestive heart failure, hypertension, age, diabetes mellitus, prior stroke/transient ischemic attack, vascular disease and sex (ie, CHA2DS2-VASc score) were determined in 470 patients with nonvalvular AF who underwent transesophageal echocardiography (TEE) to evaluate their risk of thromboembolism. Serum UA levels were similar between the low-intermediate risk (CHA2DS2-VASc score=0 or 1) and high-risk (≥2) groups, although serum D-dimer levels were lower in the low-intermediate risk than in the high-risk group. Among patients at low-intermediate risk, serum UA levels were higher in those with TEE thromboembolic risk (TEE risk: low left atrial appendage flow, spontaneous echo contrast, thrombi, or aortic atherosclerosis) than in those without TEE risk. On multivariate analysis, the serum UA level was an independent predictor of TEE risk in AF patients at low-intermediate risk (odds ratio, 1.45; 95% confidence interval 1.09-2.00; P=0.016). CONCLUSIONS: The serum UA level was associated with thromboembolic risk on TEE in patients with nonvalvular AF at low-intermediate risk stratified by clinical risk factors.

[Clinical risk stratification schemes to predict thromboembolism in patients with atrial fibrillation].

Stroke is a serious complication associated with atrial fibrillation, but the risk can vary with clinical characteristics of individual patients. CHADS2 score is the most commonly used stratification scheme because of its simplicity. However, the predictive value for ischemic stroke has been limited in patients at "low and intermediate risk". CHA2DS2-VASc score, which extends CHADS2 scheme by considering additional stroke risk factors, has been recommended to identify "truly low risk" patients who may not need any antithrombotic treatment. This new scheme could improve decision-making for thromboprophylaxis in patients with atrial fibrillation.

Effect of adaptive servoventilation on muscle sympathetic nerve activity in patients with chronic heart failure and central sleep apnea.

BACKGROUND: Adaptive servoventilation (ASV) improves cardiac function and sympathetic nerve activity in patients with heart failure (HF). However, the mechanisms underlying these improvements remain obscure. METHODS AND RESULTS: We compared muscle sympathetic nerve activity (MSNA) and cardiorespiratory polygraphy and echocardiography findings at baseline and at 3.5 ± 0.8 months' follow-up in 32 patients with HF (New York Heart Association functional class II or III; ejection fraction <45%) and central sleep apnea (CSA; apnea-hypopnea index [AHI] ≥15/h) who consented (n = 20; ASV group) or declined (n = 12; non-ASV group) to undergo ASV treatment. Compliance with ASV and changes in AHI were determined from data collected by integral counters in devices and from cardiorespiratory polygraphic findings, respectively. Ejection fraction and MSNA significantly changed in the ASV (both P < .001) but not the non-ASV group. Although changes in AHI and MSNA correlated, the average use of ASV did not. In contrast, changes in AHI and the average use of ASV were independent predictors of changes in ejection fraction (both P < .01). CONCLUSIONS: ASV decreases MSNA and improves cardiac function in association with suppression of CSA in patients with HF.

Anticoagulation control quality affects the D-dimer levels of atrial fibrillation patients.

BACKGROUND: Anticoagulation control quality affects the incidence of thromboembolic events in atrial fibrillation (AF) patients. However, the effects of anticoagulation control quality on the prothrombotic state of AF patients are unclear. METHODS AND RESULTS: Ninety-five AF patients who had been treated with warfarin were prospectively followed-up for 449 ± 92 days. We analyzed whether time in the therapeutic range (TTR) of the international normalized ratio (INR) of prothrombin time, percentage of INR values in the range (%INR), and coefficient of variation of INR values (CV-INR) were related to D-dimer levels. The mean values of TTR, %INR, and CV-INR were 62%, 59%, and 0.19, respectively, and their median values were 67%, 63%, and 0.19, respectively. TTR was significantly correlated with %INR (R(2) = 0.917, P<0.01), but not with CV-INR (R(2) = 0.050, P = 0.26). The mean and median D-dimer levels were 0.79 and 0.60 µg/ml, respectively. Low TTR, low %INR, and high CV-INR were found to contribute to high D-dimer levels (P = 0.02, 0.03, and 0.02, respectively). CONCLUSIONS: In AF patients treated with warfarin, not only the duration outside the target INR range, but also the fluctuation in INR level may influence the prothrombotic state.

Transient hypercapnic stress causes exaggerated and prolonged elevation of cardiac and renal interstitial norepinephrine levels in conscious hypertensive rats.

The responses of sympathetic nerve activity to transient stress can be exaggerated in salt-sensitive (SS), hypertensive subjects. Cardiac and renal interstitial norepinephrine (iNE) levels during and after transient hypercapnia were investigated in conscious SS rats. Dahl SS and salt-resistant (SR) 6-wk-old rats were fed a high-salt diet, and at 12 wk iNE levels in the heart and kidney were determined using microdialysis with probes inserted in the left ventricular (LV) wall and kidney. A telemetry system determined blood pressure and heart rate (HR) in separate animals. After recovery from the operation, data were collected before, during, and after exposure to normoxic 10% CO(2) for 25 min under unanesthetized conditions. The plasma NE concentrations at baseline did not differ between the two strains. Both cardiac and renal iNE levels were much higher in SS rats than in SR rats at baseline as well as during hypercapnic stress. After stress, the markedly increased iNE levels of SS rats were prolonged in the LV as well as in the kidney. During hypercapnic stress, HR decreased in both SS and SR rats, while sudden increases in HR immediately after the withdrawal from stress were followed by its slower reduction in SS rats compared with SR rats. In conclusion, transient hypercapnic stress causes exaggerated and prolonged elevation of iNE levels in the heart as well as in kidneys of SS animals.

Sex-related differences in the risk factor profile and medications of patients with atrial fibrillation recruited in J-TRACE.

BACKGROUND: Clinical characteristics, including risk factors for thromboembolism, and medications differ between men and women with atrial fibrillation (AF) in Western countries. Whether such a difference exists for Japanese patients with AF is unclear, so data from J-TRACE were used to investigate this issue. METHODS AND RESULTS: A total of 2,892 patients (2,028 men, 864 women; 70.3 years old) with AF were analyzed for the respective prevalences of risk factors and medications. CHADS2 score was calculated to determine thromboembolic risk level. Women were older (P<0.001), and more frequently had heart failure (P<0.001), and hypertension (P=0.051) than men. The proportion of subjects aged 75 years or older was higher among women than among men (P<0.001). CHADS2 score was therefore significantly higher in women than in men (2.05+/-1.29 vs 1.88+/-1.33, P<0.001). Sex-related differences were not observed for the prevalence of diabetes mellitus, myocardial infarction or ischemic stroke, nor did warfarin usage differ between men and women. CONCLUSIONS: Sex-related differences were observed in the risk factor profile and medications of Japanese patients with AF. CHADS2 score was higher in women than in men.

[A case of apical hypertrophic cardiomyopathy complicated by cardiogenic cerebral embolism].

We report a patient with apical hypertrophic cardiomyopahty (AHCM) complicated by a cardiogenic cerebral embolism. A 56-year-old man was admitted to our hospital because of a transient ischemic attack. He had been diagnosed as having AHCM at the age of 39 years. The intravenous administration of heparin was immediately started; however, he developed a weakness in his right fingers on the second day. A brain MRI examination showed multiple small infarctions in the cortex of the left frontal and temporal lobes. Transthoracic echocardiography revealed the hypokinetic movement of the myocardium and a thrombus in the apex. We suspected that the hypertrophic apex had become dilated, causing the formation of the thrombus. He then developed a cardiogenic cerebral embolism. The thrombus in the apex disappeared after the continuous administration of heparin intravenously. Here, we emphasize that patients with AHCM in the dilatation phase must receive warfarin therapy to prevent cardiogenic cerebral embolism.

Transesophageal echocardiographic thromboembolic risk is associated with smoking status in patients with atrial fibrillation.

BACKGROUND: Smoking is a risk factor for cardiovascular diseases, but it is unclear whether smoking status, including environmental tobacco smoke, increases stroke risk in patients with atrial fibrillation (AF). Abnormalities of the left atrium (LA) and aortic atherosclerosis, as detected by transesophageal echocardiography (TEE), are risk factors for stroke and thromboembolism in AF patients. We investigated the impact of smoking status on thromboembolic risk by TEE in patients with nonvalvular AF. METHODS: In 122 patients with AF (mean age, 63 years; chronic AF 50%) who underwent TEE before catheter ablation of AF or for detection of the potential cardioembolic source, urinary concentrations of cotinine and clinical variables including smoking status and the CHA2DS2-VASc score were determined. RESULTS: Severe aortic atherosclerosis and increased aortic wall thickness were more frequently detected by TEE in current smokers than in non-smokers (p<0.05), though these findings did not significantly differ between non-smokers and environmental smokers. Patients in AF rhythm during TEE, who were environmental smokers and at relatively low risk, as stratified by their CHA2DS2-VASc score (≤ 2), showed lower LA appendage flow velocity than those without environmental smoking (47±22 vs. 34±13 cm/sec, p<0.05). CONCLUSIONS: TEE findings indicated that smoking status could be associated with thromboembolic risk in patients with AF.

D-dimer level influences thromboembolic events in patients with atrial fibrillation.

BACKGROUND: Elevated coagulative molecular markers could reflect the prothrombotic state in the cardiovascular system of patients with non-valvular atrial fibrillation (NVAF). A prospective, cooperative study was conducted to determine whether levels of coagulative markers alone or in combination with clinical risk factors could predict subsequent thromboembolic events in patients with NVAF. METHODS: Coagulative markers of prothrombin fragment 1+2, D-dimer, platelet factor 4, and beta-thromboglobulin were determined at the enrollment in the prospective study. RESULTS: Of 509 patients with NVAF (mean age, 66.6 +/- 10.3 years), 263 patients were treated with warfarin (mean international normalized ratio, 1.86), and 163 patients, with antiplatelet drugs. During an average follow-up period of 2.0 years, 31 thromboembolic events occurred. Event-free survival was significantly better in patients with D-dimer level < 150 ng/ml than in those with D-dimer level>or==150 ng/ml. Other coagulative markers, however, did not predict thromboembolic events. Age (>or==75 years), cardiomyopathies, and prior stroke or transient ischemic attack were independent, clinical risk factors for thromboembolism. Thromboembolic risk in patients without the clinical risk factors was quite low (0.7%/year) when D-dimer was < 150 ng/ml, but not low (3.8%/year) when D-dimer was >or==150 ng/ml. It was >5%/year in patients with the risk factors regardless of D-dimer levels. This was also true when analyses were confined to patients treated with warfarin. CONCLUSIONS: D-dimer level in combination with clinical risk factors could effectively predict subsequent thromboembolic events in patients with NVAF even when treated with warfarin.

Cardiac sympathetic denervation modulates the sympathoexcitatory response to acute myocardial ischemia.

OBJECTIVES: This study was designed to elucidate the influence of cardiac sympathetic denervation on the sympathoexcitatory response to acute myocardial ischemia during balloon coronary occlusion (BCO) in humans. BACKGROUND: Alterations of cardiac sympathetic nerve function could modulate sympathetic reflexes originating from the ischemic area. METHODS: In 23 patients with angina pectoris, we quantified the baseline cardiac sympathetic denervation of the ischemia-related area by iodine-123 metaiodobenzylguanidine ((123)I-MIBG), and transient changes in sympathetic activity during BCO by wavelet analysis of RR interval variability. RESULTS: Balloon coronary occlusion resulted in a transient augmentation of low-frequency (LF: 0.04 to 0.14 Hz) spectral components of RR interval variability in 4 of 12 patients with cardiac denervation and in 8 of 11 patients without denervation (p < 0.01 by the chi-square test). Consequently, the increase in LF components was significantly less during BCO in patients with cardiac denervation (34%) than in those without denervation (273%) (interaction: p < 0.05). In seven patients with severe ischemia provoked by a fall of > or = 10% in the left ventricular ejection fraction, LF components increased by 506% during BCO, regardless of the condition of cardiac denervation. In contrast, in patients with mild ischemia provoked by a fall of <10% in the ejection fraction, changes of LF components during BCO were significantly less in patients with denervation than in those without denervation (84 vs. 344%, p < 0.05). CONCLUSIONS: These findings suggest that if the provoked ischemia is not severe, cardiac sympathetic denervation could prevent ischemia-induced sympathoexcitation.

[Heart failure and sudden death].

Sudden death in patients with heart failure (HF) is a topic of great complexity. Neurohumoral activation including adrenergic and renin-angiotensin-aldosterone system has been a suspected trigger for lethal ventricular arrhythmias and sudden deaths. Randomized clinical trials have demonstrated that angiotensin converting enzyme inhibitors, angiotensin II receptor antagonists and beta-adrenergic blockers improve survivals in patients with HF. Although prophylactic implantable cardioverter defibrillator (ICD) therapy is effective reducing mortality in patients with left ventricular (LV) systolic dysfunction, the ICD is unlikely to be appropriate for all patients with LV systolic dysfunction. In addition, the effect of routine prophylactic use of ICDs on health care costs must be carefully considered. The care of patients with LV systolic dysfunction should be individualized for each patient.

Impact of persistent smoking on long-term outcomes in patients with nonvalvular atrial fibrillation.

BACKGROUND: Although smoking is a risk factor for cardiovascular diseases, little is known about the impact of smoking on long-term outcomes in patients with atrial fibrillation (AF). METHODS: In 426 consecutive patients with nonvalvular AF (mean age, 66 years; 307 men; mean follow-up, 5.8±3.2 years), clinical variables including smoking status, CHADS2, and CHA2DS2-VASc score, incidences of cardiovascular events (stroke, myocardial infarction, or admission for heart failure), bleeding, and mortality were determined. RESULTS: Incidences of intracranial bleeding (0.7% vs 0.1%/year, p<0.01), all-cause mortality (4.9% vs 2.6%/year, p<0.01), and death from stroke (0.8% vs 0.2%/year, p<0.05) were higher in patients with history of smoking than in those without it. Incidence of intracranial bleeding was significantly higher in persistent smokers than in non-persistent smokers (1.2% vs 0.2%/year, p<0.01). History of smoking predicted all-cause mortality [hazard ratio (HR), 2.7; 95% confidence interval (CI), 1.7-4.5; p<0.01] and death from stroke (HR 4.7; 95% CI 1.0-22.3; p<0.05) independent of age, antithrombotic treatment, CHADS2, and CHA2DS2-VASc score. Persistent smoking predicted intracranial bleeding (HR 4.4; 95% CI 1.1-17.6; p<0.05) independent of age and antithrombotic treatment. CONCLUSIONS: Smoking status, independent of age, antithrombotic treatment, and clinical risk factors, predicted long-term adverse outcomes including bleeding events in patients with nonvalvular AF. There might be an obvious impact of persistent smoking on intracranial bleeding.

Role of central sympathoexcitation in enhanced hypercapnic chemosensitivity in patients with heart failure.

BACKGROUND: Enhanced central hypercapnic chemosensitivity is known to mediate excessive exercise ventilation and to indicate a poor prognosis in patients with chronic heart failure. The present study was designed to elucidate the role of central sympathetic activity in the enhancement of hypercapnic chemosensitivity. METHODS: Central hypercapnic chemosensitivity and plasma norepinephrine were measured in 99 patients with chronic heart failure. In 40 patients, the alpha index was derived from simultaneous analysis of R-R interval and systolic blood pressure variability. The effects of a central sympatholytic agent, guanfacine (0.25 mg/day), on hypercapnic chemosensitivity and exercise ventilatory response were studied in 20 of these patients. RESULTS: Hypercapnic chemosensitivity was enhanced in 76% of the patients and correlated significantly with plasma norepinephrine levels (r = 0.49, P < .01) at rest. There was a significant inverse relationship between central chemosensitivity and the alpha index (r = -0.41, P < .01). Guanfacine significantly reduced plasma norepinephrine levels by 29% (P < .01) and chemosensitivity by 31% (P < .01). The beneficial effect of central sympathoinhibition with guanfacine was observed specifically in patients who had enhanced chemosensitivity prior to drug administration. Similarly, the patients with excessive exercise ventilation showed a greater reduction in exercise ventilation with this agent. CONCLUSIONS: The present findings suggest that central sympathoexcitation could play an important role in the pathogenesis of enhanced hypercapnic chemosensitivity and a resultant increase in exercise ventilation in chronic heart failure.