Diastolic heart failure: restrictive cardiomyopathy,constrictive pericarditis,and cardiac tamponade: clinical and echocardiographic evaluation

An understanding of the basic principles of diastolic function is important in order to recognize diseases that may result in diastolic dysfunction and diastolic heart failure. Although uncommon, restrictive cardiomyopathy, constrictive pericarditis, and cardiac tamponade are among the disorders that may affect primarily diastolic function with preservation of systolic function. Diastolic heart failure may manifest with chronic nonspecific symptoms or may present with acute hemodynamic compromise. Echocardiography plays a vital role in the diagnosis of diastolic dysfunction and differentiation of these disease processes. It also provides a basis for clinical decisions regarding management and surgical referral. This review summarizes the clinical features, pathophysiology, and hemodynamic and echocardiographic signs of restrictive cardiomyopathy, constrictive pericarditis, and cardiac tamponade.     

Diastolic function impairment in alcoholics

BACKGROUND: Chronic excessive ethanol consumption exerts a deleterious effect on the myocardium. Although the effects of chronic alcoholism on systolic cardiac function are well known, diastolic involvement has been evaluated only partially. Therefore, we determined the presence of left ventricular diastolic impairment in chronic alcoholics and its relation with simultaneous systolic dysfunction. We also assessed the influence of ethanol consumption in diastolic impairment. METHODS: Thirty-five alcoholics with cardiomyopathy (ejection fraction < or = 50%) and 77 alcoholics with normal systolic function (ejection fraction > 50%) were evaluated. Assessment of New York Heart Association functional class, history of ethanol intake, technetium-99m radionuclide angiocardiography, and bidimensional Doppler echocardiography with evaluation of systolic and diastolic left ventricular function were performed. RESULTS: Diastolic function impairment was present in one third of the alcoholics without cardiomyopathy, compared with two thirds of the patients with cardiomyopathy (p < 0.01). A pseudonormalization phenomenon of diastolic function was observed in patients with more advanced systolic dysfunction (ejection fraction < 32%). The deterioration of the diastolic parameters correlated with ethanol consumption, regardless of age (r = 0.44, p < 0.001 for ratio of peak velocity of the transmitral flow in early diastole and peak velocity of atrial contraction flow, with lifetime dose of ethanol). CONCLUSIONS: There seems to be a dose-dependent effect of ethanol on systolic and diastolic heart function. Diastolic function impairment is present in one third of alcoholics with normal systolic function and is even more frequent when systolic dysfunction coexists.     

Diastolic dysfunction and diabetic cardiomyopathy: evaluation by Doppler echocardiography.

Doppler echocardiography has largely contributed to show the existence of a distinct diabetic cardiomyopathy. Several studies have pointed out the evidence of left ventricular (LV) remodeling and hypertrophy in alterations of both midwall systolic mechanics and LV diastolic filling in diabetes mellitus (DM), independent of the coexistence of concomitant risk factors. Further progress will be provided by new ultrasound technologies in this clinical setting. The combination of pulsed tissue Doppler study of mitral annulus with transmitral inflow may be clinically valuable for obtaining information about left ventricular filling pressure (LVFP) and unmasking Doppler inflow pseudonormal pattern, a hinge point for the progression toward advanced heart failure. In the absence of epicardial coronary artery stenosis, the ultrasound assessment of coronary flow reserve (CFR) may identify the dysfunction of coronary microcirculation, in relation with glycemic levels, insulin resistance, sympathetic overdrive, endothelial dysfunction, abnormalities of the angiotensin-renin system, and LV remodeling/hypertrophy. Diastolic dysfunction and impairment of CFR may be associated in DM, with a likely common origin. In this view, a comprehensive transthoracic Doppler evaluation of diabetic patients should include the assessment of diastolic function and estimation of LVFP by tissue Doppler, and coronary microvascular function by CFR test. Additional analysis of regional wall motion during a stress test would be required in patients with suspected coronary artery disease, another cause of diastolic dysfunction.     

Diastolic dysfunction and diabetic cardiomyopathy: evaluation by Doppler echocardiography

Doppler echocardiography has largely contributed to show the existence of a distinct diabetic cardiomyopathy. Several studies have pointed out the evidence of left ventricular (LV) remodeling and hypertrophy in alterations of both midwall systolic mechanics and LV diastolic filling in diabetes mellitus (DM), independent of the coexistence of concomitant risk factors. Further progress will be provided by new ultrasound technologies in this clinical setting. The combination of pulsed tissue Doppler study of mitral annulus with transmitral inflow may be clinically valuable for obtaining information about left ventricular filling pressure (LVFP) and unmasking Doppler inflow pseudonormal pattern, a hinge point for the progression toward advanced heart failure. In the absence of epicardial coronary artery stenosis, the ultrasound assessment of coronary flow reserve (CFR) may identify the dysfunction of coronary microcirculation, in relation with glycemic levels, insulin resistance, sympathetic overdrive, endothelial dysfunction, abnormalities of the angiotensin-renin system, and LV remodeling/hypertrophy. Diastolic dysfunction and impairment of CFR may be associated in DM, with a likely common origin. In this view, a comprehensive transthoracic Doppler evaluation of diabetic patients should include the assessment of diastolic function and estimation of LVFP by tissue Doppler, and coronary microvascular function by CFR test. Additional analysis of regional wall motion during a stress test would be required in patients with suspected coronary artery disease, another cause of diastolic dysfunction.     

Left ventricular filling

During diastole, the left ventricle receives blood from the left atrium that is subsequently ejected into the systemic circulation. In simple terms, the efficiency of left ventricular (LV) filling can be measured as the ability to receive a large volume of blood at a rapid filling rate under low filling pressures. Numerous passive and active properties of the myocardial fibers together with physical-geometric properties contribute to the process of LV filling through three primary functions: LV relaxation, LV compliance, and left atrial function. Diastolic dysfunction and diastolic heart failure therefore occur as a consequence of impairment in any one or a combination of these.     

Right ventricular filling abnormalities in acute inferior wall myocardial infarction--a pulsed Doppler study

Pulsed Doppler derived velocity profile of right ventricular filling was used to assess right ventricular diastolic function in 29 patients with acute inferior wall myocardial infarction. The peak velocities of the early filling wave 'E' and the atrial wave 'A' were measured. Diastolic dysfunction, defined as E/A ratio less than 1.0, was seen in 15 patients. Of these 15 patients, 9 had electrocardiographic evidence of right ventricular infarction and only 6 had clinical evidence of right ventricular failure. None of the 14 patients without right ventricular diastolic dysfunction (E/A ratio more than 1.0) had electrocardiographic evidence of right ventricular infarction or clinical evidence of right ventricular failure. Pulsed Doppler appears to be a sensitive technique in identifying hemodynamic derangements induced by right ventricular infarction.     

Diastolic dysfunction in exercise and its role for exercise capacity

Diastolic dysfunction is frequent in elderly subjects and in patients with left ventricular hypertrophy, vascular disease and diabetes mellitus. Patients with diastolic dysfunction demonstrate a reduced exercise capacity and might suffer from congestive heart failure (CHF). Presence of symptoms of CHF in the setting of a normal systolic function is referred to as heart failure with normal ejection fraction (HFNEF) or, if evidence of an impaired diastolic function is observed, as diastolic heart failure (DHF). Reduced exercise capacity in diastolic dysfunction results from a number of pathophysiological alterations such as slowed myocardial relaxation, reduced myocardial distensibility, elevated filling pressures, and reduced ventricular suction forces. These alterations limit the increase of ventricular diastolic filling and cardiac output during exercise and lead to pulmonary congestion. In healthy subjects, exercise training can enhance diastolic function and exercise capacity and prevent deterioration of diastolic function in the course of aging. In patients with diastolic dysfunction, exercise capacity can be enhanced by exercise training and pharmacological treatment, whereas improvement of diastolic function can only be observed in few patients.     

左心室舒张功能减低对冠心病患者左心室短轴应变率的影响

目的评价冠心病患者左心室舒张功能减低对左心室短轴应变率的影响。方法冠心病舒张功能减低患者47例,健康志愿者30名。以二尖瓣环Ea/Aa<1确定冠心病患者舒张功能减低。取左心室短轴二尖瓣水平,启动短轴多普勒组织超声,获得应变率图像。取12、4、6、8点应变率值,并取平均值。结果与健康组相比,冠心病舒张功能降低患者4点左心室基底段短轴应变率及平均应变率[2.17±0.88(1/s)比2.88±1.17(1/s),P<0.05]均降低。结论短轴平均应变率可作为评价左心室舒张功能的一种简便方法。     

Prognostic significance of right ventricular dysfunction in patients with acute inferior myocardial infarction and right ventricular involvement

Little is known about the influence of right ventricular (RV) dysfunction on prognosis of patients with acute inferior myocardial infarction (IMI) and RV involvement. Therefore, 99 consecutive patients (mean age 56.6 ± 3.4 years) with RV involvement during acute IMI were followed for a 12-month period to clarify the influence of acute RV dysfunction on short- and long-term survivals. Forty-one patients with IMI evolved with severe arterial hypotension due to RV dysfunction, while 58 patients had no hemodynamic impairment due to RV involvement. Basal hemodynamic data (mean ± SD) for patients with RV dysfunction were blood pressure (BP) 92/59 ± 22/20 mmHg, systemic vascular resistance (SVR) 2314 ± 252 dynes·s·cm^?5, and cardiac index (CI) 1.3 ± 0.31/min/m². Patients without RV dysfunction demonstrated BP 113/74 ± 20/16 mmHg (p≤0.05), SVR 1324 ± 354 dynes·s·cm^?5 (p≤0.01), and CI 2.6 ± 0.5 1/min/m² (p≤0.05). Angiographic differences noted were that hemodynamically compromised patients showed lower RV ejection fractions (0.27 ± 0.08) than patients without hemodynamic disturbance [0.41 ± 0.11 (p≤0.05)]; however, left ventricular ejection fractions were 0.48 ± 0.10 and 0.52 ± 0.12, respectively. Short- and long-term mortality rates were assessed during the follow-up period. Patients with hemodynamic impairment due to RV infarction had a higher mortality rate for the first month and for 11 subsequent months post MI than patients without hemodynamic impairment, that is, 24.4 vs. 6.9 and 14.6 (p≤0.05) vs. 3.4% (p≤0.05), respectively. These data suggest that decreased RV ejection fraction possibly is linked with significantly reduced short- and long-term survival in patients with RV involvement during acute IMI.     

Ischemic mitral valve repair: predictive significance of restrictive left ventricular diastolic filling

AIM: The aim of the present study was to evaluate the impact of left ventricular (LV) diastolic filling impairment on postoperative results in patients with low LV ejection fraction (EF) undergoing combined coronary artery bypass grafting (CABG) and mitral valve (MV) repair. METHODS AND RESULTS: Study population consisted of 53 patients with ischemic MV incompetence and LV systolic dysfunction (mean EF-26.1 +/- 6%), who underwent CABG with MV repair. Patients were divided into three groups according to the LV diastolic filling pattern. Study protocol included evaluation of perioperative mortality (30 days inhospital mortality), NYHA functional class, and two-dimensional Doppler echocardiographic examination preoperatively, 10-14 days, and 12 months after surgery. The highest perioperative mortality rate (33.3%), unimproved functional status (in 78.5% of the patients, NYHA functional class remained unchanged late after surgery), and hemodynamic deterioration (LV dilatation, progression of mitral regurgitation (MR) was observed in the restriction group). Though early after surgery, MR reduction was significant in this group, at even one year after surgery 85.7% of patients presented with >grade 1 of MR (P < 0.05). Logistic regression analysis showed that restrictive LV diastolic filling is an important independent preoperative marker (P = 0.035) of progression of MR late after MV repair. CONCLUSION: In patients with severe LV dysfunction undergoing combined CABG and MV repair, restrictive LV diastolic filling pattern is an important preoperative marker of high perioperative mortality rate, further negative remodeling of LV, and progression of mitral regurgitation late after MV repair.     

血浆BNP水平在老年COPD患者呼吸机脱机中的评估

<正>接受机械通气的慢性阻塞性肺病(COPD)急性加重患者常常存在脱机困难[1]。呼吸力学加重和所产生的呼吸肌疲劳、肺动脉嵌压升高、急性左心室缺血、左心室射血分数下降和右心室扩大伴随室间隔左移位[2]是脱机失败的主要原因。COPD患者常出现呼气流速受限导致的肺动态充气过度,提示存在内在呼     

Surgical treatment of degenerative mitral regurgitation

Between October 1965 and April 1975, mitral valve replacement was performed In 66 patients with myxomatous degeneration of the mitral valve (“floppy valve syndrome”). Operative mortality was 6 percent (four patients). Current evaluation was obtained for all patients; the average postoperative follow-up interval for surviving patients was 3.5 years (range 1 month to 9.9 years); the total duration of postoperative follow-up for all patients was 180 patient-years. Overall survival rates, calculated by the actuarial method, were 81, 68 and 50 percent, respectively, 1, 2 and 5 years after mitral valve replacement.Preoperative variables with a significantly adverse effect on patient survival included patient age greater than 50 years, New York Heart Association functional class IV, left ventricular end-diastolic pressure greater than 12 mm Hg and mean pulmonary arterial wedge pressure greater than 16 mm Hg. Support is advanced for the concept that mitral valve dysfunction associated with myxomatous degeneration constitutes a broad spectrum of clinicopathologic involvement. Acute clinical and hemodynamic deterioration may often occur in the setting of chronic mitral valve dysfunction. Postoperative mortality is directly related to preoperative functional disability and hemodynamic evidence of impaired left ventricular function. Consideration should be given to earlier operative intervention in patients with myxomatous mitral degeneration and mitral insufficiency before severe and probably irreversible impairment of ventricular function occurs.     

Diastolic dysfunction is an independent risk factor for death in patients with sickle cell disease.

OBJECTIVES: The goal of this study was to characterize left ventricular diastolic function in the sickle cell disease (SCD) population and to relate echocardiographic measures of dysfunction with pulmonary hypertension and mortality. BACKGROUND: Pulmonary hypertension has been identified as a predictor of death in the adult SCD population. Although diastolic dysfunction is also observed in this population, its prevalence, association with high pulmonary artery systolic pressure, and attributable mortality remain unknown. METHODS: Diastolic function assessment using tissue Doppler imaging was performed in a group of 141 SCD patients. Conventional echocardiographic parameters of diastolic function were performed in a total of 235 SCD patients. RESULTS: Diastolic dysfunction was present in 18% of patients. A combination of diastolic dysfunction and pulmonary hypertension was present in 11% of patients, and diastolic dysfunction accounted for only 10% to 20% of the variability in tricuspid regurgitation (TR) jet velocity. Diastolic dysfunction, as reflected by a low E/A ratio, was associated with mortality with a risk ratio of 3.5 (95% confidence interval 1.5 to 8.4, p < 0.001), even after adjustment for tricuspid regurgitation (TR) jet velocity. The presence of both diastolic dysfunction and pulmonary hypertension conferred a risk ratio for death of 12.0 (95% confidence interval 3.8 to 38.1, p < 0.001). CONCLUSIONS: Diastolic dysfunction and pulmonary hypertension each contribute independently to prospective mortality in patients with SCD. Patients with both risk factors have an extremely poor prognosis. These data support the implementation of echocardiographic screening of adult patients with SCD to identify high-risk individuals for further evaluation.     

Critical care issues following orthotopic liver transplantation

Orthotopic liver transplantation (OLT) remains a formidable undertaking. A multidisciplinary approach to pre-operative optimization and intra- and postoperative care of patients undergoing OLT increases the chance of a successful outcome. Although there have been moves towards avoidance of Intensive Care Unit (ICU) admission for "routine" OLT recipients, critical care practitioners continue to play a key role in liver transplant programs in the MELD era. Use of protocolized care delivery and innovative ICU therapeutic interventions have streamlined the pre-operative optimization and perioperative care of OLT recipients. The postoperative course is significantly influenced by the patient's pre-operative status, the intraoperative course and the function of the liver graft. In addition to discussion of general ICU concepts such as the use of prognostic scoring systems and protocolization of care, this review will use an organ-system based approach to describe the postoperative ICU care of OLT recipients. We discuss hemodynamic management, ventilator weaning, optimization of sedation and analgesia, and the investigation and management of renal and metabolic abnormalities. In addition, we examine postoperative complications including hemorrhage, central nervous system pathology and graft dysfunction. The review concludes with a discussion of the additional challenges practitioners face when dealing with living donor liver transplantation and donation after cardiac death.     

Silent brain injury after cardiac surgery: a review: cognitive dysfunction and magnetic resonance imaging diffusion-weighted imaging findings

The appearance of cognitive dysfunction after cardiac surgery in the absence of focal neurologic signs, a poorly understood but potentially devastating complication, almost certainly results from procedure-related brain injury. Confirmation of the occurrence of perioperative silent brain injury has been developed through advances in magnetic resonance imaging (MRI) techniques. These techniques detect new brain lesions in 25% to 50% of patients after both coronary artery bypass graft and valve surgery. Use of post-operative cognitive dysfunction as a marker of brain injury is problematic because of potential difficulties in ascertainment. It can be hypothesized that post-operative appearance of MRI lesions may serve as a more objective marker of brain injury in research efforts. If MRI examination can be used in this way, then 2 vitally important questions can be addressed. 1) What is the frequency of important, but silent, brain injury during cardiac surgery? 2) Does long-term cognitive impairment ensue? This review briefly discusses clinical features of post-operative cognitive dysfunction and reviews the evidence supporting a possible association with MRI evidence of perioperative brain injury and its potential for long-term dementia. We conclude that this association is plausible, but not yet firmly established.     

Calcium antagonists and left ventricular function

Calcium antagonists impede the entry of calcium into myocytes and inhibit myocardial contraction. Calcium antagonists differ in their relative negative inotropic potency and can provoke baroreceptor stimulation that modulates left ventricular (LV) performance. Calcium antagonists are uniformly well tolerated in patients with normal LV function. Use of these agents in patients with suspected LV function impairment has yielded results ranging from hemodynamic improvement to clinical deterioration and increased mortality. Reports of clinical deterioration when calcium antagonists were combined with beta blockers underscore the importance of reflex adrenergic support for the myocardium. Although calcium antagonists are potent vasodilators and produce short-term hemodynamic improvement, they are not useful as primary treatment in patients with congestive heart failure (CHF). They may have a place in the treatment of coexistent problems in patients with LV dysfunction. Short-term use of calcium antagonists for myocardial ischemia or rapid atrial fibrillation is probably safe in the presence of LV dysfunction and overt CHF. Calcium antagonists appear to have a role in the treatment of patients with diastolic dysfunction of diverse etiologies.     

Load Dependent Diastolic Dysfunction in Heart Failure

Congestive heart failure may result from cardiovascular overload, from systolic or from diastolic dysfunction. Diastolic left ventricular dysfunction may result from structural resistance to filling such as induced by pericardial constraint, right ventricular compression, increased chamber stiffness (hypertrophy) and increased myocardial stiffness (fibrosis). A distinct and functional etiology of diastolic dysfunction is slow and incomplete myocardial relaxation. Relaxation may be slowed by pathological processess such as hypertrophy, ischemia and by asynchronous left ventricular function. The present contribution analyses the occurrence of slow and incomplete myocardial relaxation in response to changes in systolic pressure and in response to changes in venous return. The regulation of myocardial relaxation by load is critically dependent on the transition from myocardial contraction to relaxation, which occurs in dogs when 82% of peak isovolumetric pressure has developed or at a relative load of 0.82. This corresponds to early ejection in normal hearts, but is situated even before aortic valve opening in severely diseased hearts. When load is developed beyond this transition, relaxation becomes slow and even incomplete. This is load dependent diastolic dysfunction. Load dependent diastolic dysfunction occurs in normal hearts facing heavy afterload and in severely diseased hearts even with normal hemodynamic parameters. This dysfunction should contribute to elevating filling pressures in most patients with severe congestive heart failure. This dysfunction can be reverted by decreasing systolic pressures or by decreasing venous return. Load dependent diastolic dysfunction gives us an additional reason to agressively treat CHF patients with diuretics and vasodilators.     

Improved survival rates support left ventricular assist device implantation early after myocardial infarction

OBJECTIVES

Implantation of left ventricular assist devices (LVADs) early after acute myocardial infarction (MI) has traditionally been thought to be associated with high mortality rates due to technical limitations and severe end-organ dysfunction. At some experienced centers, doctors have refrained from earlier operation after MI to allow for a period of hemodynamic and end-organ stabilization.

METHODS

We retrospectively investigated the effect of preoperative MI on the survival rates of 25 patients who received a Thermocardiosystems Incorporated LVAD either <2 weeks (Early) (n = 15) or >2 weeks (Late) (n = 10) after MI. Outcome variables included perioperative right ventricular assistance (and right-sided circulatory failure), hemodynamic indexes, percent transplanted or explanted, and mortality.

RESULTS

No statistically significant differences were demonstrated between demographic, perioperative or hemodynamic variables between the Early and Late groups. Patients in the Early group demonstrated a lower rate of perioperative mechanical right ventricular assistance, but had a higher rate of perioperative inhaled nitric oxide use. In addition, 67% of patients in the Early group survived to transplantation and 7% to explantation, findings comparable to those in the Late group (60% and 0% respectively).

CONCLUSIONS

This clinical experience suggests that patients may have comparable outcomes whether implanted early or late after acute MI. These data therefore support the early identification and timely application of this modality in post-MI LVAD candidates, as this strategy may also reveal a subgroup of patients for whom post-MI temporary LVAD insertion may allow for full ventricular recovery.     

Percutaneous right ventricular support during catheter ablation of intra-atrial reentrant tachycardia in an adult with a mustard baffle—A novel use of the Impella device

Late sequelea following a Mustard operation for transposition of the great arteries (TGA) include atrial arrhythmias and dysfunction of the systemic right ventricle. Catheter mapping and ablation of atrial tachycardia in the setting of significant right ventricular dysfunction may result in hemodynamic compromise. We report the novel use of the Impella percutaneous microaxial flow pump to support cardiac output in an adult patient with a Mustard operation for TGA who experienced a cardiac arrest during a prior ablation attempt. The Impella device was placed via a retrograde approach across the aortic valve into the right ventricle providing hemodynamic stability for successful mapping and ablation of intra-atrial reentrant tachycardia.     

呼吸机引起的膈肌功能障碍与脱机肺水肿的研究进展

膈肌功能障碍和脱机引起的肺水肿是导致脱机失败的两个重要原因。膈肌功能障碍会降低膈肌收缩力量,使肺通气减少,引起脱机失败;脱机时胸内负压增大,通过增加静脉回流和左心室后负荷,导致脱机肺水肿和呼吸窘迫。本文对膈肌功能障碍和脱机引起的肺水肿的发生机制、诊断方法以及治疗策略进行综述。