心钠肽在急性心力衰竭治疗中的研究进展

治疗急性心力衰竭的传统药物,如:利尿剂、血管扩张剂、肾上腺素能受体激动剂、磷酸二酯酶抑制剂等不仅作用单一,而且各有其局限性。血浆心钠肽具有扩血管、利尿、拮抗神经内分泌激素的多种作用。基因重组人心钠肽与内源性心钠肽具有相同的生物学作用,对急性心力衰竭的治疗已经显示出良好的效果。     

检测血心钠肽水平对舒张性心力衰竭的诊断意义

目的:探讨测定血心钠肽(ANP)水平对诊断舒张性心力衰竭(DHF)的意义.方法:选择66例DHF患者作为实验组、64例非DHF的呼吸困难患者作为对照组,应用酶联免疫吸附测定法(ELISA)测定其血清ANP和脑钠素(BNP)水平,同时行心脏B超检查.并据ANP水平等对实验组和对照组进行分析判断.结果:DHF组的ANP水平...     

Amiodarone Decreases Plasma Brain Natriuretic Peptide Level in Patients with Heart Failure and Ventricular Tachyarrhythmia

Brain natriuretic peptide (BNP) is a powerful neurohormonal marker of left ventricular function and prognosis. Amiodarone either has no effect or improves the haemodynamics in patients with left ventricular dysfunction, but its effect on BNP is unknown. This study evaluated the effect of amiodarone on plasma BNP level in patients with heart failure and ventricular tachyarrhythmia.Plasma BNP level was studied in 46 patients with heart failure ventricular tachyarrhythmia, before (baseline) and at week 2 and months 1, 3 and 6 of amiodarone treatment. In addition, 21 patients with heart failure and ventricular tachyarrhythmia, who received an implantable cardioverter defibrillator, but not amiodarone, were studied on the same schedule. All patients had previously received potent vasodilator and beta-blocker therapy. Echocardiography and Holter monitoring were also performed.Amiodarone significantly decreased plasma BNP levels at week 2 to month 6 during therapy. Heart rates and frequencies of premature ventricular complexes were markedly reduced by amiodarone. Echocardiographic findings did not show a change in left ventricular end-diastolic dimensions, despite a slight increase in fraction shortening at month 6 during amiodarone therapy. The above parameters showed no change in patients without amiodarone. The effect of heart rate, premature ventricular complexes, fraction shortening, serum creatinine or thyroid stimulating hormone level was not significantly associated with decrease in BNP level during amiodarone therapy by a multivariate analysis. Among amiodarone-treated patients, mortality was higher in 24 with BNP levels 100 pg/ml at month 6 than in 22 with BNP levels <100 pg/ml during a mean follow-up period of 31 months.Amiodarone appears to have a decreasing effect on plasma BNP level, as well as an antiarrhythmic effect, in patients with heart failure and ventricular tachyarrhythmia.     

Atrial Fibrillation in Heart Failure:

Atrial fibrillation and congestive heart failure are commonly occurring cardiac disorders that often exist concomitantly. The prognostic significance of the presence or absence of atrial fibrillation, as an independent risk factor, in patients with heart failure remains controversial. Antiarrhythmic drugs with good hemodynamic profiles and neutral effects on survival are preferred treatments for converting atrial fibrillation and maintaining sinus rhythm. Other standard therapies for congestive heart failure, such as angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and beta-blockers also have a role in the treatment of these coexisting disease states. The article presents an overview of atrial fibrillation in patients with heart failure and reviews the prevalence, prognostic significance, and efficacy of various antiarrhythmic agents for the conversion and maintenance of sinus rhythm. (J Cardiovasc Electrophysiol, Vol. 14, pp. S281-S286, December 2003, Suppl.)     

氨基末端B型利钠肽前体与心房颤动的研究进展

目前氨基末端B型利钠肽前体正广泛应用于临床试验和心血管研究中,近年的研究显示心房颤动与氨基末端B型利钠肽前体水平升高有关。现主要就近年来关于氨基末端B型利钠肽前体作为危险因子和预测因素在心房颤动治疗方面的研究进展进行综述。     

B‐type Natriuretic Peptide and Amino‐terminal Pro‐B‐type Natriuretic Peptide in Pediatric Patients with Pulmonary Arterial Hypertension

Objectives. B‐type natriuretic peptide (BNP) and the amino‐terminal fragment (NTproBNP) correlate with clinical variables, but have not been simultaneously studied in a large number of pediatric patients with pulmonary arterial hypertension (PAH). The purpose of our investigation was to compare BNP and NTproBNP with clinical indicators of disease in a pediatric PAH population for which biomarkers are much needed. Design. We retrospectively compared BNP and NTproBNP levels with exercise capacity, echocardiographic data, and hemodynamics in PAH patients under 21 years old. Two hundred sixty‐three blood samples from 88 pediatric PAH patients were obtained, with BNP and NTproBNP drawn at the same time. Results. There was a correlation between BNP and NTproBNP with mean pulmonary arterial pressure/mean systemic arterial pressure ratio (r= 0.40, P < .01; r= 0.45, P < .01; respectively), mean right atrial pressure (r= 0.48, P < .01; r= 0.48, P < .01), and tricuspid regurgitant velocity (r= 0.36, P < .01; r= 0.41, P < .01). BNP and NTproBNP are associated with 6‐minute walk distance, mean pulmonary arterial pressure, mean pulmonary arterial pressure/mean systemic arterial pressure ratio, mean right atrial pressure, pulmonary vascular resistance index, and tricuspid regurgitant velocity when investigated longitudinally. On the average, a 1‐unit increase in log BNP or NTproBNP was associated with 4.5 units × m² or 3.4 units × m² increase in pulmonary vascular resistance index, respectively. There was a strong correlation between log BNP and log NTproBNP measurements (r= 0.87, P < .01). Conclusion. In pediatric PAH, BNP and NTProBNP are strongly correlated and predict changes in clinical variables and hemodynamics. In a cross‐sectional analysis, NTproBNP correlated with echocardiographic and exercise data better than BNP; NTproBNP showed less within patient variability over time; therefore, NTproBNP can add additional information toward predicting these clinical measurements.     

B-Type Natriuretic Peptide: Spectrum of Application. Nesiritide (Recombinant BNP) for Heart Failure

The therapeutic goals for patients hospitalized with acutely decompensated heart failure are to reverse acute hemodynamic abnormalities, relieve symptoms, and to initiate heart failure therapies which will decrease disease progression and improve long-term survival. Nesiritide (recombinant B-type natriuretic peptide) is the first in a new class of therapeutic agents for the treatment of heart failure and has been demonstrated to offer a unique combination of safety and efficacy. The use of nesiritide on top of standard care including diuretic therapy, has been proven to lead to meaningful clinical benefits in a broad range of acutely decompensated heart failure patients. Nesiritide is an attractive therapeutic option because of its more rapid and sustained hemodynamic profile, more favorable effects on neurohormonal suppression, with less adverse effects than alternative intravenous heart failure treatments such as nitroglycerine, nitroprusside, dobutamine, or milrinone. The use of nesiritide is the most effective initial treatment approach among currently available strategies to reverse acutely decompensated heart failure and to facilitate optimization of the heart failure medical regimen.     

Different Patterns of Angiotensin II and Atrial Natriuretic Peptide Secretion in a Sheep Model of Atrial Fibrillation

INTRODUCTION: It is well established that rapid atrial rates, as in atrial fibrillation (AF), cause atrial electrical and structural remodeling leading to the maintenance of AF. The role of neurohumoral changes in this pathophysiologic vicious circle remains unclear. METHODS AND RESULTS: We followed the concentrations of angiotensin II (AT II) and atrial natriuretic peptide (ANP) in a sheep model of AF. The sheep were atrially paced at 600 beats/min for 15 weeks. Electrophysiologic study was performed at regular intervals, and venous blood samples were taken. There was a slow increase in the vulnerability for AF. The cumulative incidence of sustained AF was 80% after 15 weeks of pacing. This increased vulnerability for AF was accompanied by atrial electrical remodeling and an increase in atrial pressure. AT II increased rapidly and stayed elevated: 17+/-4 pg/mL at baseline, and 40+/-11 and 39+/-7 pg/mL after 1 and 12 weeks of pacing, respectively. ANP rose more progressively: 35+/-7 pg/mL at baseline, and 72+/-17, 95+/-10, and 106+/-23 pg/mL after 1, 3, and 12 weeks, respectively. ANP levels correlated with atrial pressure and inducibility of AF. There was no relation between these parameters and AT II levels. CONCLUSION: AT II and ANP increased significantly in this animal model of AF. Elevation of AT II occurs early and seems to be dependent on rapid atrial rate rather than the presence of AF. ANP increased more progressively. It paralleled the inducibility of AF and atrial stretch. Both neurohumoral pathways may form a potential therapeutic target for treatment of patients with AF.     

糖尿病并发冠心病血浆内皮素及心钠肽含量变化及其临床价值

目的测定2型糖尿病（T2DM）并发冠心病（CHD）病人血浆血管内皮素（ET）、心钠素（ANP）含量，探讨其在本病发生与发展中的作用和对临床诊断的价值。方法选择64例糖尿病（DM）病人，其中并发CHD组32例，未并发CHD组32例，以放射免疫分析（Rn）法检测血浆ET、ANP水平，进行分析，并与30名健康体检者作比较。结果DM并发CHD组血浆ET、ANP含量显著高于未并发CHD的DM组及正常健康人组（P〈0．01）；DM无并发CHD组血浆ET、ANP含量显著高于正常对照组（P〈0．05）。影响因素除与本身有无并发CHD外，尚与病程、年龄有关。结论DM并发CHD病人血浆KF、ANP变化可能参与了本病的发病过程。可作为判断病情程度及疗效评价的指标。     

心脏利钠肽类激素在心力衰竭诊断中的应用进展

心力衰竭是很多心血管疾病的最终转归,心脏利钠肽类激素(CNH)作为心力衰竭诊断的新指标近年来颇受重视。由于CNH种类较多又各具特点,故现通过综述近年来CNH在心力衰竭诊断方面的研究结果以比较不同CNH临床应用价值。     

脑钠肽结合超声多普勒评价舒张性心力衰竭患者的心功能

目的 采用血浆脑钠肽(BNP)浓度测定结合超声多普勒心动图的参数来评价舒张性心力衰竭患者的心功能,为临床提供判断舒张性心力衰竭及其严重程度的敏感和特异的客观指标.方法 选择舒张性心力衰竭患者85例(心力衰竭组),按纽约心脏病学会(NYHA)心功能分级,Ⅱ级31例、Ⅲ级36例、Ⅳ级18例,以及健康对照组30例.测定血浆BNP浓度,超声多普勒结合组织多普勒显像(TDI)测定左室结构、左室舒张功能及左室舒张末压.结果 舒张性心力衰竭患者血浆BNP浓度明显高于对照组(P<0.001),且随心力衰竭程度加重而逐渐升高(P<0.001).舒张性心力衰竭组左房内径(LA)、室间隔厚度(IVS)、左室后壁厚度(LVPW)、舒张早期流速峰值/舒张早期速度峰值(E/Em)较对照组升高,E/舒张晚期流速峰值(A)降低(P<0.01),血浆BNP浓度与E/A比值呈负相关(r=-0.634,P<0.01),与E/Em比值呈正相关(r=0.728,P<0.01).结论 血浆BNP浓度测定结合超声多普勒心动图的参数判断舒张性心力衰竭患者的心功能简便准确.     

Spontaneous Transition from Atrial Fibrillation to Typical Atrial Flutter during Catheter Ablation of the Pulmonary Vein

A 71-year-old male patient was admitted for catheter ablation of the pulmonary veins to treat paroxysmal atrial fibrillation. Atrial fibrillation originating from the left superior pulmonary vein was induced after a pause of atrial pacing under isoproterenol infusion and became sustained. Spontaneous transition from atrial fibrillation to typical atrial flutter was noted after complete isolation of the pulmonary vein focus from the left atrium. Subsequently linear ablation of the cavotricuspid isthmus was created with completely bi-directional isthmus conduction block. We hypothesized that ectopic pulmonary vein focus played an important role in the spontaneous conversion of atrial fibrillation to typical atrial flutter, and complete isolation of the pulmonary vein could stop the spontaneous transition between the two atrial tachyarrhythmias.     

Heat‐Stress Responses Modulate Beta‐Adrenergic Agonist and Angiotensin II Effects on the Arrhythmogenesis of Pulmonary Vein Cardiomyocytes

Effect of Heat Stress on Pulmonary Vein Cardiomyocytes. Introduction: Heat stress‐induced responses reduce the occurrence of atrial fibrillation (AF). Pulmonary vein (PV) cardiomyocytes with pacemaker activity play a critical role in the pathophysiology of AF. In this study, we examined whether heat‐stress responses alter the electrophysiological characteristics of PV cardiomyocytes and protect the PV against angiotensin II‐ or isoproterenol‐induced arrhythmogenesis. Methods and Results: We used whole‐cell patch clamp techniques to investigate the spontaneous activity and ionic currents in single isolated rabbit PV pacemaker cardiomyocytes with or without (control) exposure to heat stress (43°C, 15 minutes) 5 ± 1 hours before the experiments. Compared to control cardiomyocytes, heat‐stressed PV cardiomyocytes had slower beating rates. Heat‐stressed PV cardiomyocytes had larger L‐type calcium currents, transient outward currents, smaller inward rectifier potassium currents, but similar sodium‐calcium exchanger currents_. Additionally, heat‐stressed PV cardiomyocytes had a lower incidence of pacemaker currents than control PV cardiomyocytes. Moreover, isoproterenol increased the beating rate of control cardiomyocytes but not heat‐stressed PV cardiomyocytes. Similarly, angiotensin II also increased the beating rate of control cardiomyocytes, but not heat‐stressed PV cardiomyocytes, in association with decreased expression of the angiotensin II type 1 receptor. Conclusion: Heat‐stress responses altered the electrophysiological characteristics of PV cardiomyocytes and attenuated the effects of isoproterenol and angiotensin II on PV arrhythmogenesis, which may play a role in the protective potential of heat‐stress responses. (J Cardiovasc Electrophysiol, Vol. 22, pp. 183‐190, February 2011)     

Catheter Ablation of Long‐Standing Persistent Atrial Fibrillation: A Lesson from Circumferential Pulmonary Vein Isolation

Catheter Ablation of Long‐Standing Persistent AF. Introduction: Circumferential pulmonary vein isolation (CPVI) is associated with a high success rate in patients with paroxysmal and persistent atrial fibrillation (AF). However, in patients with long‐standing persistent AF, the ideal ablation strategy still remains a matter of debate. Methods and Results: Two‐hundred and five patients underwent catheter ablation for long‐standing persistent AF defined as continuous AF of more than 1‐year duration. In a first step, all patients underwent CPVI. If direct‐current cardioversion failed following CPVI, ablation of complex fractionated atrial electrograms (CFAEs) was performed. The goal was conversion into sinus rhythm (SR) or, alternatively, atrial tachycardia (AT) with subsequent ablation. A total of 340 procedures were performed. CPVI alone was performed during 165 procedures in 124 of 205 (60.5%) patients. In the remaining 81 patients, additional CFAE ablation was performed in 45, left linear lesions for recurrent ATs in 44 and SVC isolation in 15 patients, respectively, resulting in inadvertent left atrial appendage isolation in 9 (4.4%) patients. After the initial ablation procedure, 67 of 199 patients remained in SR during a mean follow‐up of 19 ± 11 months. Six patients were lost to follow‐up. After a mean of 1.7 ± 0.8 procedures, 135 of 199 patients (67.8%) remained in SR. Eighty‐six patients (43.2%) remained in SR following CPVI performed as the sole ablative strategy. Conclusions: CPVI alone is sufficient to restore SR in 43.2% of patients with long‐standing persistent AF. Multiple procedures and additional ablation strategies with a significant risk of inadvertent left atrial appendage isolation are often required to maintain stable SR. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1085‐1093)