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Making a firm diagnosis of chronic heart failure with preserved ejection fraction (HFpEF) remains a challenge. We recommend a new stepwise diagnostic process, the ‘HFA–PEFF diagnostic algorithm’. Step 1 (P=Pre‐test assessment) is typically performed in the ambulatory setting and includes assessment for heart failure symptoms and signs, typical clinical demographics (obesity, hypertension, diabetes mellitus, elderly, atrial fibrillation), and diagnostic laboratory tests, electrocardiogram, and echocardiography. In the absence of overt non‐cardiac causes of breathlessness, HFpEF can be suspected if there is a normal left ventricular (LV) ejection fraction, no significant heart valve disease or cardiac ischaemia, and at least one typical risk factor. Elevated natriuretic peptides support, but normal levels do not exclude a diagnosis of HFpEF. The second step (E: Echocardiography and Natriuretic Peptide Score) requires comprehensive echocardiography and is typically performed by a cardiologist. Measures include mitral annular early diastolic velocity (e′), LV filling pressure estimated using E/e′, left atrial volume index, LV mass index, LV relative wall thickness, tricuspid regurgitation velocity, LV global longitudinal systolic strain, and serum natriuretic peptide levels. Major (2 points) and Minor (1 point) criteria were defined from these measures. A score ≥5 points implies definite HFpEF; ≤1 point makes HFpEF unlikely. An intermediate score (2–4 points) implies diagnostic uncertainty, in which case Step 3 (F1: Functional testing) is recommended with echocardiographic or invasive haemodynamic exercise stress tests. Step 4 (F2: Final aetiology) is recommended to establish a possible specific cause of HFpEF or alternative explanations. Further research is needed for a better classification of HFpEF.  相似文献   
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Aims/hypothesis

Hyperglycaemia and insulin resistance have been linked to diastolic dysfunction experimentally. We investigated the association between glucose metabolism and diastolic function along the whole spectrum of glucose metabolism states.

Methods

In the observational Diagnostic Trial on Prevalence and Clinical Course of Diastolic Dysfunction and Diastolic Heart Failure (DIAST-CHF) study, patients with risk factors for heart failure were included. We analysed data including comprehensive echocardiography from a subgroup of patients classified by OGTT and history as normal (n?=?343), prediabetic (n?=?229) and non-insulin treated (n?=?335) or insulin-treated (n?=?178) type 2 diabetic.

Results

While ejection fraction did not differ, markers of diastolic function significantly worsened across groups. Prediabetes represented an intermediate between normal glucose metabolism and diabetes with regard to echocardiography changes. Prevalence and severity of diastolic dysfunction increased significantly (p?<?0.001) along the diabetic continuum. Glucose metabolism status was significantly associated with prevalence of diastolic dysfunction on multivariate logistic regression analysis. In the whole cohort, HbA1c correlated with early diastolic mitral inflow velocity (E):early diastolic tissue Doppler velocity at mitral annulus (e′) ratio (E:e′) (r?=?0.20, p?<?0.001). HbA1c was significantly associated with E:e′ on multivariate analysis. Similarly, glucose metabolism status was significantly associated with E:e′ on multivariate analysis. The distance walked in 6 min decreased along the diabetic spectrum and was significantly correlated with E:e′ and grade of diastolic dysfunction.

Conclusions/interpretation

Glucose metabolism is associated with diastolic dysfunction across the whole spectrum. Our data extend previous observations into the prediabetic and normal range, and may be relevant to preventive approaches, as no effective treatment has been identified for diastolic heart failure once established.  相似文献   
5.

Objectives

To evaluate the 9‐month safety and efficacy of polymer‐free sirolimus eluting drug eluting stents in septuagenarians and octogenarians.

Methods

An all‐comer, worldwide single armed trial ( ClinicalTrials.gov Identifier NCT02629575) was conducted to demonstrate the safety and efficacy of an ultra‐thin strut, polymer‐free sirolimus eluting stent (PF‐SES). The primary endpoint was the 9‐month target revascularization rate (TLR). Secondary endpoints included the rates of major adverse cardiac events (MACE), stent thrombosis (ST) and bleeding (BARC) in septuagenarians (≥70 years, <80 years), and in octogenarians (≥80 years) to be compared to the younger patient group (<70 years).

Results

A total of 1607 patients were treated with PF‐SES in the sub‐70‐year‐old age group, 694 in septuagenarians, and 371 in the octogenarian patient group. At 9 months, the MACE rates were 7.2% in octogenarians, 5.3% in septuagenarians, and 3.0% in the younger patient group (P = 0.001). These were mostly driven by all‐cause mortality (4.4% vs 1.9% vs 0.6%, P < 0.001) while the TLR rates were only numerically lower in the younger age group (P = 0.080). BARC 1‐5 bleeding events were more frequent in the older age group (1.9% vs 2.7% vs 4.6%, P = 0.012) whereas the rates for ST were not different (0.7% vs 0.6% vs 0.6%, P = 0.970).

Conclusions

In octogenarians treated with PF‐SES, the rates for MACE, overall mortality, and bleeding are higher as compared to the younger age groups. However, the rates for TLR and ST were not significantly different across the investigated age groups. PF‐SES are safe and effective in octogenarians.
  相似文献   
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Myocardial contractility depends on temperature. We investigated the influence of mild hypothermia (37–31°) on isometric twitch force, sarcoplasmic reticulum (SR) Ca2+-content and intracellular Ca2+-transients in ventricular muscle strips from human and porcine myocardium, and on in vivo hemodynamic parameters in pigs. In vitro experiments: muscle strips from 5 nonfailing human and 8 pig hearts. Electrical stimulation (1 Hz), simultaneous recording of isometric force and rapid cooling contractures (RCCs) as an indicator of SR Ca2+-content, or intracellular Ca2+-transients (aequorin method). In vivo experiments: 8 pigs were monitored with Millar-Tip (left ventricular) and Swan-Ganz catheter (pulmonary artery). Hemodynamics parameters were assessed at baseline conditions (37°), and after stepwise cooling on cardiopulmonary bypass to 35, 33, and 31°C. Hypothermia increase isometric twitch force significantly by 91 ± 16% in human and by 50 ± 9% in pig myocardium (31 vs. 37°C; p < 0.05, respectively). RCCs or aequorin light emission did not change significantly. In anesthetized pigs, mild hypothermia resulted in an increase in hemodynamic paramters of myocardial contractility. While heart rate decreased from 111 ± 3 to 73 ± 1 min−1, cardiac output increased from 2.4 ± 0.1 to 3.1 ± 0.3 l/min, and stroke volume increased from 21 ± 1 to 41 ± 3 ml. +dP/dtmax increased by 25 ± 8% (37 vs. 31°C; p < 0.05 for all values). Systemic and pulmonary vascular resistance did not change significantly during cooling. Mild hypothermia exerts significant positive inotropic effects in human and porcine myocardium without increasing intracellular Ca2+-transients or SR Ca2+-content. These effects translate into improved hemodynamics parameters of left ventricular function. Received: 26 June 2000, Returned for revision: 20 July 2000, Revision received: 11 October 2000, Accepted: 17 October 2000  相似文献   
7.
OBJECTIVE: Heart failure is associated with reduced function of sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a) but increased function of sarcolemmal Na+/Ca2+ exchanger (NCX), leading to decreased SR Ca2+ content and loss of frequency-potentiation of contractile force. We reported that SERCA2a-overexpression in transgenic rat hearts (TG) results in improved contractility. However, it was not clear whether TG have improved contractility due to frequency-dependent improved SR Ca2+ handling. METHODS: Therefore, we characterized TG (n=35) vs. wild-type (WT) control rats (n=39) under physiological conditions (37 degrees C, stimulation rate <8 Hz). Twitch force, intracellular Ca2+ transients ([Ca2+]i), and SR Ca2+ content were measured in isolated muscles. The contribution of transsarcolemmal Ca2+ influx (I(Ca)) through L-type Ca2+ channels (LTCC) and reverse mode NCX (I(Na/Ca)) to Ca2+ cycling were studied in isolated myocytes. RESULTS: With increasing frequency, force increased in TG muscles by 168+/-35% (8 Hz; P<0.05) and SR Ca2+ content increased by maximally 118+/-31% (4 Hz; P<0.05). In WT, there was a flat force-frequency response without changes in SR Ca2+ content. Relaxation parameters of force and [Ca2+]i decay were accelerated at each frequency in TG vs. WT by approximately 10%. At prolonged rest intervals (<240 s), force and SR Ca2+ content increased significantly more in TG. Consequently, absolute SR Ca2+ content measured in myocytes was increased approximately 2-fold in TG. Transsarcolemmal Ca2+ fluxes estimated by I(Ca) (at 0 mV -10.2+/-1.1 vs. -16.9+/-1.3 pA/pF) and I(Na/Ca) (0.17+/-0.02 vs. 0.46+/-0.05 pA/pF) were decreased in TG vs. WT (P<0.05), whereas NCX and LTCC protein expression was only slightly reduced (P=n.s.). CONCLUSION: In summary, SERCA2a-overexpression improved contractility in a frequency-dependent way due to increased SR Ca2+ loading whereas transsarcolemmal Ca2+ fluxes were decreased.  相似文献   
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The purpose of the present study was to characterize adenosine receptors in human atrial and ventricular myocardium. In isolated electrically driven preparations, adenosine produced "direct" negative inotropic effects in atrial myocardium (AT). In ventricular myocardium (VE), it only had negative inotropic properties when force of contraction had been stimulated with isoprenaline ("indirect" effect), but it has no inotropic effect alone. The adenosine receptor antagonist 8-phenyltheophylline antagonized the "direct" and "indirect" effects; these findings indicated that both effects were mediated by adenosine receptors. In cardiac membranes from human AT and VE, adenosine receptors were characterized with [3H]-8-cyclopentyl-1,3-dipropylxanthine (DPCPX) binding. The effects of agonists R-(-)-N6-phenylisopropyladenosine (R-PIA), S-(+)-N6-phenylisopropyladenosine (S-PIA), and 5'-(N-ethylcarboxamido) adenosine (NECA) and the effects of guanine nucleotides [Gpp(NH)p] were studied also. The antagonist affinities as judged from the apparent affinity, Kd, of [3H]DPCPX were similar in AT (2.2 nmol/l; 95% confidence limits, 1.4-3.7) and VE (1.8 nmol/l; 95% confidence limits, 1.0-3.0). The number of adenosine receptors was 1.7 times greater in AT (26.9 +/- 2.33 fmol/mg protein; n = 5) than in VE (16.2 +/- 2.3 fmol/mg protein; n = 5). High and low affinity states of adenosine receptors evaluated with the influence of Gpp(NH)p on agonist competition with R-PIA were similar in AT or VE. The rank orders of potency for agonists (R-PIA greater than S-PIA greater than NECA) and antagonists (DPCPX greater than 8-phenyltheophylline greater than theophylline) were characteristic for the A1 receptor subtype. It is concluded that A1 adenosine receptors exist in the human myocardium. Since binding properties were similar in AT and VE, the same A1 adenosine receptor probably couples to different effectors in a similar guanine nucleotide-dependent way. [3H]DPCPX is the first radiolabeled antagonist ligand that allows detection of A1 adenosine receptors and their coupling in the human myocardium.  相似文献   
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