Small heart with low cardiac output for orthostatic intolerance in patients with chronic fatigue syndrome

Background:

The etiology of chronic fatigue syndrome (CFS) is unknown. Orthostatic intolerance (OI) is common in CFS patients. Recently, small heart with low cardiac output has been postulated to be related to the genesis of both CFS and OI.

Hypothesis:

Small heart is associated with OI in patients with CFS.

Methods:

Study CFS patients were divided into groups of 26 (57%) CFSOI(+) and 20 (43%) CFSOI(?) according to the presence or absence of OI. In addition, 11 OI patients and 27 age‐ and sex‐matched control subjects were studied. Left ventricular (LV) dimensions and function were determined echocardiographically.

Results:

The mean values of cardiothoracic ratio, systemic systolic and diastolic pressures, LV end‐diastolic dimension, LV end‐systolic dimension, stroke volume index, cardiac index, and LV mass index were all significantly smaller in CFSOI(+) patients than in CFSOI(?) patients and healthy controls, and also in OI patients than in controls. A smaller LV end‐diastolic dimension (<40 mm) was significantly (P<0.05) more prevalently noted in CFSOI(+) (54%) and OI (45%) than in CFSOI(?) (5%) and controls (4%). A lower cardiac index (<2 L/min/mm²) was more prevalent in CFSOI(+) (65%) than in CFSOI(?) (5%, P<0.01), OI (27%), and controls (11%, P<0.01).

Conclusions:

A small size of LV with low cardiac output was noted in OI, and its degree was more pronounced in CFSOI(+). A small heart appears to be related to the genesis of OI and CFS via both cerebral and systemic hypoperfusion. CFSOI(+) seems to constitute a well‐defined and predominant subgroup of CFS. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.

     

Do Pre‐Hemodialysis Estimates of Extracellular Volume Excess Using Bioimpedance and N‐Terminal Brain Natriuretic Peptide Correlate With Cardiac Chamber Size Measured by Magnetic Resonance Imaging?

Bioimpedance can be used to measure extracellular water (ECW) and total body water in hemodialysis (HD) patients and estimate ECW excess. However, ECW excess potentially includes both an increase in the plasma volume and also the extravascular volume. Overestimating the amount of fluid to be removed during HD risks intra‐dialytic hypotension. We wished to determine the association between estimates of ECW excess comparing several different equations using bioimpedance, brain N‐terminal pro‐brain natriuretic peptide (NT‐proBNP) with cardiac chamber volumes and function as determined by cardiac magnetic resonance imaging pre‐HD measurements of ECW and total body water were made using multifrequency bioimpedance and cardiac chamber sizes and function were determined by magnetic resonance imaging. Thirty patients, 20 males (66.7%), mean age 64.4 ± 15.3 years were studied. ECW and ECW/height were positively associated with indexed right ventricular end‐systolic (RVESVi) and end‐diastolic volume (RVEDVi) (RVESi r = 0.46, r = 0.43; RVEDi r = 0.50, r = 0.44, all P < 0.05), but not with left sided cardiac volumes. Whereas NT‐proBNP was associated with indexed left atrial and ventricular size (r = 0.47, r = 0.58, P < 0.05), but not right sided cardiac volumes. Pre‐HD NT‐proBNP was associated with left sided cardiac chamber sizes, but not with right sided chamber sizes, whereas ECW/height was associated with right sided cardiac chamber sizes. As right‐sided cardiac chamber size is more responsive to and reflective of changes in intravascular volume than the left atrium and ventricle, then bioimpedance measured ECW is potentially more reliable in estimating plasma volume expansion.     

Hemodialysis patients with less extracellular water overload and smaller cardiac atrial chamber sizes are at greater risk of a fall in blood pressure during dialysis

Intradialytic hypotension is the most common complication of hemodialysis (HD) treatments. Excessive ultrafiltration results in reduced cardiac preload. We aimed to determine whether a fall in systolic blood pressure during HD was greater in patients starting HD with (a) less overhydration measured by extracellular water (ECW) and (b) lower cardiac preload by cardiac magnetic resonance imaging (MRI). Pre‐HD measurements of ECW and total body water (TBW) were performed using multifrequency bioimpedance (MFBIA). Cardiac chamber sizes and functions were determined by MRI. Twenty‐six patients, 18 males (69.2%), 11 (42.3%) with diabetes, mean age 63.9 ± 15.9 years were studied. Systolic blood pressure (SBP) fell in 15 (57.7%) patients, and either did not change or increased in 9. There was no difference in demographics between groups. Patients with a fall in SBP had lower pre‐HD ECW/TBW (0.400 ± 0.018 vs 0.418 ± 0.021), indexed right ventricular end‐diastolic volume (81.2 ± 37.6 vs 100.8 ± 33.7 mL/m²), and indexed left atrial size (13.7 ± 3.9 vs 18.3 ± 5.0 mL/m²), all P < .05, respectively. There were univariate correlations between the change in SBP and pre‐HD ECW/TBW for the trunk (r = .50, P = .009) and indexed left atrial volume (r = .54, P = .005). A fall in blood pressure occurred more commonly in patients starting HD with lower overhydration as measured by bioimpedance, and those with smaller cardiac chamber sizes. Patients with the lowest ECW/TBW and smallest cardiac chamber sizes had the greatest falls in SBP. This study reinforces the importance of determining physiological target weights and avoiding inappropriately low target weights for HD patients.     

Abnormalities in pH handling by peripheral muscle and potential regulation by the autonomic nervous system in chronic fatigue syndrome

Abstract. Jones DEJ, Hollingsworth KG, Taylor R, Blamire AM, Newton JL (From the Institute of Cellular Medicine, Newcastle Magnetic Resonance Centre, and Institute for Ageing and Health, Newcastle University, UK). Abnormalities in pH handling by peripheral muscle and potential regulation by the autonomic nervous system in chronic fatigue syndrome. J Intern Med 2010; 267 : 394–401. Objectives. To examine muscle acid handling following exercise in chronic fatigue syndrome (CFS/ME) and the relationship with autonomic dysfunction. Design. Observational study. Setting. Regional fatigue service. Subjects & interventions. Chronic fatigue syndrome (n = 16) and age and sex matched normal controls (n = 8) underwent phosphorus magnetic resonance spectroscopy (MRS) to evaluate pH handling during exercise. Subjects performed plantar flexion at fixed 35% load maximum voluntary contraction. Heart rate variability was performed during 10 min supine rest using digital photophlethysmography as a measure of autonomic function. Results. Compared to normal controls, the CFS/ME group had significant suppression of proton efflux both immediately postexercise (CFS: 1.1 ± 0.5 mmol L^?1 min^?1 vs. normal: 3.6 ± 1.5 mmol L^?1 min^?1, P < 0.001) and maximally (CFS: 2.7 ± 3.4 mmol L^?1 min^?1 vs. control: 3.8 ± 1.6 mmol L^?1 min^?1, P < 0.05). Furthermore, the time taken to reach maximum proton efflux was significantly prolonged in patients (CFS: 25.6 ± 36.1 s vs. normal: 3.8 ± 5.2 s, P < 0.05). In controls the rate of maximum proton efflux showed a strong inverse correlation with nadir muscle pH following exercise (r² = 0.6; P < 0.01). In CFS patients, in contrast, this significant normal relationship was lost (r² = 0.003; P = ns). In normal individuals, the maximum proton efflux following exercise were closely correlated with total heart rate variability (r² = 0.7; P = 0.007) this relationship was lost in CFS/ME patients (r² < 0.001; P = ns). Conclusion. Patients with CFS/ME have abnormalities in recovery of intramuscular pH following standardised exercise degree of which is related to autonomic dysfunction. This study identifies a novel biological abnormality in patients with CFS/ME which is potentially open to modification.     

Cardiac Structure and Function and Renal Insufficiency in the Oldest Old

Background:

People over the age of 85 years have a high incidence of cardiovascular disease and chronic kidney disease.

Hypothesis:

There is an association between renal function and cardiac structure and function in subjects 85 years of age.

Methods:

Subjects born in the years 1920 and 1921 were recruited from the Jerusalem Longitudinal Cohort Study. Echocardiography was performed at the subject's home with assessment of cardiac structure and function. Glomerular filtration rate (GFR) was assessed by the Cockroft‐Gault formula, with abnormal GFR defined as ≤60 mL/min/1.73 m².

Results:

There were 310 subjects who were enrolled. When GFR was examined as a continuous variable, linear regression showed a small although statistically significant relationship between GFR and left atrial volume (r = 0.15, P < 0.014), left ventricular mass index (r = 0.12, P < 0.04), and ejection fraction (r = 0.19, P < 0.03) but not with indices of diastolic function (r = 0.02, P < 0.72). However, using the accepted clinical cutoff of 60 mL/min/1.73 m², there were no significant differences between subjects with normal and abnormal GFR in indices of cardiac structure. Ejection fraction (57.0 ± 10.4% vs 54.4 ± 10.3%; P = 0.08) and indices of diastolic function (E/e′ 12.4 ± 5.0 vs 12.3 ± 4.6; P = 0.89) were not significantly different between the 2 groups.

Conclusions:

A weak and clinically insignificant association was found between GFR as a continuous variable and indices of cardiac function. However, using the clinically accepted cutoff, no association between abnormal GFR and cardiac structure or function was observed. David Leibowitz, MD, and Yoram Maaravi, MD, contributed equally to this report. The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Systolic Right Ventricular Function in Children and Young Adults with Pulmonary Artery Hypertension Secondary to Congenital Heart Disease and Tetralogy of Fallot: Tricuspid Annular Plane Systolic Excursion (TAPSE) and Magnetic Resonance Imaging Data

Objective. The tricuspid annular plane systolic excursion (TAPSE), as echocardiographic index to assess right ventricular (RV) systolic function, has not been investigated thoroughly in children and young adults with tetralogy of Fallot (TOF) and pulmonary artery hypertension secondary to congenital heart disease (PAH‐CHD). Patients. TAPSE values of 49 patients with PAH‐CHD and 156 patients with TOF were compared with age‐matched normal subjects. TAPSE values were also compared with RV ejection fraction (RVEF) and RV indexed end‐diastolic volume (RVEDVi) determined by magnetic resonance imaging in PAH‐CHD and TOF patients. Results. Patients with a PAH‐CHD showed a positive correlation between TAPSE with RVEF (r= 0.81; P < 0.001) and a negative correlation between TAPSE with RVEDVi (r=?0.67; P < 0.001). Similarly, in our TOF patients, a positive correlation between TAPSE with RVEF (r= 0.65; P < 0.001) and a negative correlation between TAPSE with RVEDVi (r=?0.42; P < 0.001) was seen. Conclusions. Significant pressure overload in PAH‐CHD patients and volume overload in TOF patients lead to a decreased systolic RV function, determined by TAPSE and magnetic resonance imaging and to increased RVEDVi values, determined by MRI, with time.     

Effects of mechanical left ventricular unloading by impella on left ventricular dynamics in high‐risk and primary percutaneous coronary intervention patients

Objectives : We studied online left ventricular (LV) dynamic effects of mechanical LV unloading directly after percutaneous coronary intervention (PCI). Background : Limited clinical information is available on the direct LV dynamic consequences of LV unloading in patients undergoing high‐risk PCI and primary PCI for acute ST‐elevation myocardial infarction. Methods : The effects of the Impella LP2.5 device on LV dynamics were studied in 11 patients (elective high‐risk PCI, n = 6; primary PCI, n = 5). LV pressure and volume were continuously assessed by a pressure‐conductance catheter at 4 different support levels of the Impella, from 0 L/min at baseline to 2.5 L/min at maximal support. Results : The response to increased LV unloading was not different between both groups of patients. The pooled data showed no change on global and systolic LV function during increased LV unloading, while diastolic function showed improvement as indicated by an increased LV compliance in all patients. There was a decrease in end‐diastolic pressure from 22 ± 12 to 13 ± 9 mm Hg (P = 0.0001), in end‐diastolic elastance from 0.134 ± 0.060 to 0.091 ± 0.064 mm Hg/mL (P = 0.009), and in end‐diastolic wall stress from 84 ± 50 to 47 ± 39 mm Hg (P = 0.004). Conclusions : LV unloading decreases end‐diastolic wall stress and improves diastolic compliance dose‐dependently. Our results indicate beneficial LV unloading effects of Impella during high‐risk and primary PCI. © 2009 Wiley‐Liss, Inc.     

Electrocardiographic QRS Duration Reflects Right Ventricular Remodeling in Patients Undergoing Corrective Surgery for Isolated Tricuspid Regurgitation: A Comparative Study with Cardiac Magnetic Resonance Imaging

Background:

The role of electrocardiogram (ECG) is unclear for the longitudinal follow‐up of patients who undergo corrective surgery for isolated severe tricuspid regurgitation (TR).

Hypothesis:

This study sought to investigate the usefulness of changes in QRS duration of ECG after TR surgery in predicting right ventricular (RV) reverse remodeling as determined by cardiac magnetic resonance imaging (CMR).

Methods:

We enrolled 30 consecutive TR patients (27 women, aged 57.8 ± 9.6 years) who had undergone prior left‐sided valve surgery. A computer‐assisted analysis was performed for objective calculation of QRS duration before and after surgery.

Results:

At a median CMR follow‐up of 27.5 months postsurgery, QRS duration was cut by 14.6%, from 110.4 ± 14.6 msec to 96.9 ± 11.9 msec (P < 0.001), while CMR showed a decrease in RV end‐diastolic volume index (RV‐EDVI) from 179.5 ± 59.7 to 119.1 ± 30.4 mL/m² (P < 0.001). QRS duration correlated significantly with RV‐EDVI and RV end‐systolic volume index (r = 0.65, P < 0.001 and r = 0.53, P < 0.001, respectively), and a percent change in QRS duration was significantly correlated with a percent change in RV‐EDVI (r = 0.40, P = 0.03). When significant RV reverse remodeling was defined as a reduction in RV‐EDVI ≥20% following TR surgery, the sensitivity and specificity for significant RV reverse remodeling were 75% and 78%, respectively, with a 9% reduction in QRS duration (P = 0.01, area underneath the receiver operator curve [AUC] = 0.81).

Conclusions:

The extent of changes in postoperative QRS duration can be used as a useful, inexpensive, and simple index reflecting the occurrence of significant RV reverse remodeling in patients undergoing corrective TR surgery. Clin. Cardiol. 2012 doi: 10.1002/clc.22030 First two authors equally contributed to this work. This study was supported in part by grants from the Korea Health 21 R&D Project, Ministry of Health and Welfare, Republic of Korea (A090064) and Leading Foreign Research Institute Recruitment Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (MEST) (0640‐20100001). The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Association between Oxidative Stress Assessed by Urinary 8-Hydroxydeoxyguanosine and the Cardiac Function in Hypertensive Patients without Overt Heart Disease

Although increased oxidative stress is known to be associated with worsened cardiac function in chronic heart failure, consensus is still lacking regarding the association between oxidative stress and cardiac function in hypertensive patients without overt heart disease. This study aimed to evaluate the association between oxidative stress assessed by urinary 8-hydroxydeoxyguanosine (8-OHdG) and cardiac function in hypertensive patients without overt heart disease. We enrolled a total of 80 hypertensive patients (70 ± 11 y) who had been taking antihypertensive medications for at least 1 year. Urinary 8-OHdG levels were measured by an immunochromatographic assay (ICR-001, Selista Inc., Tokyo, Japan). Echocardiography was performed to assess the left ventricular (LV) diastolic function by measuring early diastolic mitral annular velocity (e′) and the ratio of early transmitral flow velocity (E) to e′ (E/e′). Urinary 8-OHdG was correlated with E/e′ (r = 0.346, P = .002), e′ (r = ?0.310, P = .005), and HbA1c (r = 0.276, P = .013). Multiple linear regression analysis revealed that only e′ (β = ?0.343, P = .004) was an independent determinant of urinary 8-OHdG. In conclusion, decreased e′ is independently associated with elevated urinary 8-OHdG, a marker of oxidative stress, in hypertensive patients. Therefore, an elevated urinary 8-OHdG level may be useful in detecting subclinical LV diastolic dysfunction in hypertensive patients without overt heart disease.     

Predicting hyperresponse among pacemaker-dependent nonischemic cardiomyopathy patients upgraded to cardiac resynchronization

Resynchronizing Pacemaker‐Dependent Patients. Introduction: Right ventricular (RV) pacing engenders left ventricular (LV) dyssynchrony and may diminish LV systolic function, promote adverse cardiac remodeling, and foster heart failure (HF). This process may be reversible in some pacemaker‐dependent patients upgraded to cardiac resynchronization therapy (CRT). We examined the clinical characteristics of pacemaker‐dependent patients who exhibit hyperresponse (i.e., normalization of LV function) with CRT upgrade. Methods and Results : We identified 51 chronically RV‐paced patients with no coronary artery disease, LV ejection fraction (EF) ≤ 35%, and severe HF symptoms who were upgraded to CRT‐defibrillators (CRT‐D). Echocardiograms were performed before and ≥6 months after CRT. Patients with follow‐up LVEF ≥ 50% were deemed hyperresponders. Clinical outcomes of death, cardiac transplant, mechanical circulatory support, and HF hospitalizations were assessed. Fifteen patients were CRT hyperresponders; all demonstrated ≥15% relative LV end‐systolic volume decrease. Hyperresponders had smaller baseline LV dimensions and shorter known cardiomyopathy duration than nonhyperresponders (P < 0.01). The best predictors of hyperresponse using receiver operating characteristic analysis were LV end‐systolic dimension <48 mm (area under the curve [AUC] 0.92, P < 0.001), LV end‐diastolic dimension <58 mm (AUC 0.86, P < 0.001), and cardiomyopathy duration <24 months (AUC 0.82, P < 0.001). No hyperresponders died, received a cardiac transplant, or required mechanical circulatory support during 42 ± 22 months follow‐up, whereas 5 nonhyperresponders died, 2 underwent transplant, and 1 required an assist device (log rank P = 0.049). Conclusion : Among chronically RV paced patients who are upgraded to CRT‐D, smaller baseline LV dimensions and shorter known cardiomyopathy duration predict hyperresponse. Hyperresponders have excellent long‐term survival. (J Cardiovasc Electrophysiol, Vol. 22, pp. 905‐911, August 2011)     

Variability and Resource Utilization of Bedside Three‐dimensional Echocardiographic Quantitative Measurements of Left Ventricular Volume in Congenital Heart Disease

Objectives. This study evaluated the variability and time resource utilization of bedside 3‐dimensional echocardiographic left ventricular volume analysis (3D‐LVVA) in congenital heart disease (CHD). Background. There are currently limited data on the resource utilization and variability of 3D‐LVVA in the CHD. Methods. Four reviewers of varying experience levels were timed performing 15 on‐scanner 3D‐LVVAs. Inter‐ and intraobserver variability for left ventricular end‐diastolic volume (LVEDV), end‐systolic volume (LVESV), and ejection fraction (LVEF) was evaluated. Results. Median age was 12.7 years (0.6–33 years). Diagnoses were: normal (n = 4), cardiomyopathy (n = 4), ventricular septal defect (n = 2), and atrioventricular canal, tricuspid atresia, bicuspid aortic valve, left ventricular hypertrophy, and heart transplant (n = 1 each). For interobserver variability, intraclass correlation coefficients (ICCs) for all possible combinations of reviewers were: LVEDV, 0.991–0.999 (P < .01); LVESV, 0.98–0.99 (P < .01); LVEF, 0.95–0.98 (P < .01). Bland–Altman plot mean differences (±2SD) were: LVEDV, ?3 ± 14%; LVESV, ?5.4 ± 21.4%; LVEF, 1.2 ± 14.7%. Interobserver variability of LVESV was not dependent on ventricular volumes (P = .25; r² = 0.01) or heart rate (P = .43; r² = 0.003). For intraobserver variability, ICCs for 2 reviewers were LVEDV, 0.99, 0.99 (P < .01); LVESV, 0.99, 0.99 (P < .01); and LVEF, 0.94, 0.94 (P < .01), respectively. Bland–Altman plot mean differences (±2SD) were: LVEDV, ?1 ± 9.2%; LVESV, 0 ± 19.6%; LVEF, ?2.2 ± 24%. Conclusion. Reviewers with varying experience levels can accomplish 3D‐LVVA at the bedside with acceptable inter‐ and intraobserver reproducibility, providing the rationale for integrating 3D‐LVVA into the care of CHD patients.     

Impairment of cardiac function and remodeling induced by myocardial infarction in rats are attenuated by the nonpeptide angiotensin-(1-7) analog AVE 0991

Aims: We evaluated effects of the nonpeptide angiotensin (ANG)‐(1–7) analog AVE 0991 (AVE) on cardiac function and remodeling as well as transforming growth factor‐beta1 (TGF‐β1)/tumor necrosis factor‐alpha (TNF‐α) expression in myocardial infarction rat models. Methods and Results: Sprague–Dawley rats underwent either sham surgery or coronary ligation. They were divided into four groups: sham, control, AVE, and AVE + A‐779 [[D‐Ala⁷]‐ANG‐(1–7), a selective antagonist for the ANG‐(1–7)] group. After 4 weeks of treatment, the AVE group displayed a significant elevation in left ventricular fractional shorting (LVFS) (25.5 ± 7.3% vs. 18.4 ± 3.3%, P < 0.05) and left ventricular ejection fraction (LVEF) (44.8 ± 7.6% vs. 32.7 ± 6.5%, P < 0.05) when compared to the control group, but no effects on the left ventricular end‐diastolic and end‐systolic diameters (LVDd and LVDs, respectively) were observed. In addition, we found that the myocyte diameter (18 ± 2 μm vs. 22 ± 4 μm, P < 0.05), infarct size (42.6 ± 3.6% vs. 50.9 ± 4.4%, P < 0.001) and collagen volume fraction (CVF) (16.4 ± 2.2% vs. 25.3 ± 3.2%, P < 0.001) were significantly reduced in the AVE group when compared to the control group. There were no differences in LVFS, LVEF, myocyte diameter, and infarct size between the control and AVE+A‐779 groups. AVE also markedly attenuated the increased mRNA expression of collagen I (P < 0.001) and collagen III (P < 0.001) and inhibited the overexpression of TGF‐β1 (P < 0.05) and TNF‐α (P < 0.05) compared to the control group. Conclusion: AVE could improve cardiac function and attenuate ventricular remodeling in MI rat models. It may involve the inhibition of inflammatory factors TGF‐β1/TNF‐α overexpression and the action on the specific receptor Mas of ANG‐(1–7).     

Favorable Effects of Vasodilators on Left Ventricular Remodeling in Asymptomatic Patients With Chronic Moderate‐Severe Aortic Regurgitation and Normal Ejection Fraction: A Meta‐Analysis of Clinical Trials

Background:

The role of vasodilator therapy in asymptomatic patients with chronic moderate to severe aortic regurgitation (AR) and normal left ventricular (LV) function is uncertain. We assessed the effects of vasodilator therapy (hydralazine, calcium channel blockers, and angiotensin‐converting enzyme inhibitors) in this subgroup of patient population.

Hypothesis:

Vasodilators have favorable effects on LV remodelling in asymptomatic patients with chronic moderate to severe aortic regurgitation and normal LV function.

Methods:

We performed a systematic literature search for randomized clinical trials using long‐term vasodilator therapy in asymptomatic patients with chronic severe AR and normal LV function. The magnitude of difference between the vasodilator and nonvasodilator groups was assessed by computing the mean difference (MD). Heterogeneity of the studies was analyzed by Cochran Q statistics. The MD for LV ejection fraction, LV end systolic volume index, and LV end diastolic volume index were computed by random effects model. The MD for LV end‐systolic diameter and LV end‐diastolic diameter were computed by fixed effects model. A 2‐sided alpha error <0.05 was considered to be statistically significant.

Results:

Seven studies with 460 patients were included. Meta‐analysis of the studies revealed a significant increase in LVEF (MD: 5.32, 95% confidence interval [CI]: 0.37 to 10.26, P = 0.035), a significant decrease in LV end diastolic volume index (MD: ?16.282, 95% CI: ?23.684 to ?8.881, P < 0.001), and a significant decrease in LV end diastolic diameter (MD: ?2.343, 95% CI: ?3.397 to ?1.288, P < 0.001) in the vasodilator group compared with the nonvasodilator group. However, there was no significant decrease in LV end systolic volume index (MD: ?6.105, 95% CI: ?12.478 to 0.267, P = 0.060) or in LV end systolic diameter (MD: 0.00, 95% CI: ?0.986 to 0.986, P = 1.0) in the vasodilator group compared with the nonvasodilator group.

Conclusions:

In asymptomatic patients with chronic severe AR and normal LV function, vasodilators have favorable effects on LV remodeling. Clin. Cardiol. 2012 doi: 10.1002/clc.22019 The authors have no funding, financial relationships, or conflicts of interest to disclose.

     

Effect of bivalirudin compared with unfractionated heparin plus abciximab on infarct size and myocardial recovery after primary percutaneous coronary intervention: the horizons-AMI CMRI substudy

Background : Myocardial infarct size is a strong independent predictor of mortality in patients with ST‐elevation myocardial infarction (STEMI). In the Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction (HORIZONS‐AMI) trial, bivalirudin compared with unfractionated heparin plus a glycoprotein IIb/IIIa inhibitor reduced cardiac mortality in STEMI patients, which was attributed to reduced major bleeding. Whether a possible reduction in infarct size with bivalirudin may have contributed to the enhanced survival with this agent is unknown. Methods : Cardiac magnetic resonance imaging was performed within 7 days and after 6 months in 51 randomized patients from a single center in HORIZONS‐AMI trial (N = 28 bivalirudin, N = 23 heparin plus abciximab). Infarct size, microvascular obstruction (MVO), left ventricular ejection fraction (LVEF), and LV end‐diastolic and end‐systolic volume indices were evaluated. Results : Infarct size was not significantly different after treatment with bivalirudin compared with heparin plus abciximab either within 7 days (median 9.3% [interquartile range 4.9%, 26.6%] vs. 20.0% [5.9%, 28.2%], P = 0.28) or at 6 months 6.7% [3.8%, 20.0%] vs. 8.2% [1.8%, 16.5%], P = 0.73). MVO was present in 28.6% versus 34.8% of patients respectively (P = 0.63). LVEF and LV volume indices also did not significantly differ between the two groups at either time period, nor were differences in myocardial recovery evident. Conclusions : In conclusion, in the HORIZONS‐AMI Cardiac magnetic resonance imaging (CMRI) substudy, cardiac magnetic resonance imaging within 7 days and at 6 months after primary percutaneous coronary intervention (PCI) did not demonstrate significant differences in infarct size, MVO, LVEF, or LV volume indices in patients treated with bivalirudin compared with unfractionated heparin plus abciximab. © 2011 Wiley Periodicals, Inc.     

Fatigue severity remains stable over time and independently associated with orthostatic symptoms in chronic fatigue syndrome: a longitudinal study

Abstract. Jones DEJ, Gray J, Frith J, Newton JL (UK NIHR Biomedical Centre in Ageing, Institute of Cellular Medicine, Institute for Ageing and Health, Newcastle University, Newcastle, UK) Fatigue severity remains stable over time and independently associated with orthostatic symptoms in chronic fatigue syndrome: a longitudinal study. J Intern Med 2011; 269 : 182–188. Objectives: To examine fatigue variability over time in chronic fatigue syndrome (CFS) and the effect of other symptoms on its predictability. Design: Longitudinal cohort study of patients with CFS (Fukuda criteria). Setting: Specialist CFS clinical service. Subjects: Phase 1: 100 patients who participated in a study of CFS symptoms in 2005 were revisited in 2009. Phase 2: 25 patients completed fatigue diaries to address intra‐ and inter‐day variability in perceived fatigue. Main outcome measures: Phase 1: subjects completed fatigue impact scale (FIS), Epworth sleepiness scale (ESS), orthostatic grading scale (OGS) and hospital anxiety and depression scale (HADS). Changes in variables represented the differences between 2005 and 2009. Phase 2: subjects rated fatigue on a scale of 0 (no fatigue) to 10 (severe fatigue) four times a day for 5 weeks. Results: Symptom assessment tools were available in both 2005 and 2009 for 74% of patients. FIS and HADS depression (HAD‐D) and anxiety (HAD‐A) scores significantly improved during follow‐up whereas ESS and OGS remained stable. FIS improved in 29/74 (39%) subjects, and by ≥10 points in 19 (26%). FIS worsened by ≥10 points in 33/74 (45%) subjects. On multivariate analysis, independent predictors of current fatigue (FIS in 2009) were FIS in 2005, HAD‐D in 2009, OGS in 2009 and change in HAD‐A. Reported fatigue was stable from week to week and from day to day. Patients reported higher fatigue in the morning (mean ± SD; 6.4 ± 2), becoming significantly lower at lunchtime (6.2 ± 2; P < 0.05) and increasing again to 7 ± 2 at bedtime. Conclusions: Current fatigue is independently associated with current autonomic symptom burden, current depression and change in anxiety during follow‐up. These findings have implications for targeted symptom management in CFS.     

Left ventricular end‐diastolic volume predicts exercise capacity in patients with a normal ejection fraction

Background

Exercise capacity is a powerful predictor of all‐cause mortality. The duration of exercise with treadmill stress testing is an important prognostic marker in both healthy subjects and patients with cardiovascular disease. Left ventricular (LV) structure is known to adapt to sustained changes in level of physical activity.

Hypothesis

Poor exercise capacity in patients with a preserved LV ejection fraction (LVEF) should be reflected in smaller LV dimensions, and a normal exercise capacity should be associated with larger LV dimensions, irrespective of comorbidities.

Methods

This hypothesis was first tested in a cross‐sectional analysis of 201 patients with normal chamber dimensions and preserved LVEF who underwent a clinically indicated treadmill stress echocardiogram using the Bruce protocol (derivation cohort). The best LV dimensional predictor of exercise capacity was then tested in 1285 patients who had a Bruce‐protocol treadmill exercise stress test and a separate transthoracic echocardiogram (validation cohort).

Results

In the derivation cohort, there was a strong positive relationship between exercise duration and LV end‐diastolic volume deciles (r ² = 0.85; P < 0.001). Regression analyses of several LV dimensional parameters revealed that the body surface area–based LV end‐diastolic volume index was best suited to predict exercise capacity (P < 0.0001). In a large validation cohort, LV end‐diastolic volume was confirmed to predict exercise capacity (P < 0.0001).

Conclusions

Among patients referred for outpatient stress echocardiography who have a preserved LVEF and no evidence of myocardial ischemia, we found a strong positive association between LV volume and exercise capacity.     

Abnormal left ventricular torsion and cardiac autonomic dysfunction in subjects with type 1 diabetes mellitus

Left ventricular torsion is increased and cardiac energetics are reduced in uncomplicated type 1 diabetes mellitus (T1DM). Our aim was to determine the relationships of these abnormalities to cardiovascular autonomic neuropathy (CAN) in subjects with T1DM. A cross-sectional study was conducted in 20 subjects with T1DM free of known coronary heart disease attending an outpatient clinic. Cardiovascular autonomic neuropathy was assessed using heart rate variability studies and the continuous wavelet transform method. Left ventricular function was determined by speckle tracking echocardiography. Magnetic resonance spectroscopy and stress magnetic resonance imaging were used to measure cardiac energetics and myocardial perfusion reserve index, respectively. Twenty subjects (age, 35 ± 8 years; diabetes duration, 16 ± 9 years; hemoglobin A_1c, 8.0% ± 1.1%) were recruited. Forty percent of the subjects exhibited definite or borderline CAN. Log peak radial strain was significantly increased in subjects with CAN compared with those without (1.56 ± 0.06 vs 1.43 ± 0.14, respectively; P = .011). Data were adjusted for log duration of diabetes, and log left ventricular torsion correlated (r = 0.593, P = .01) with log low-frequency to high-frequency ratio during the Valsalva maneuver. Log isovolumic relaxation time correlated significantly with log Valsalva ratio and log proportion of differences in consecutive RR intervals of normal beats greater than 50 milliseconds during deep breathing. However, CAN did not correlate with cardiac energetics or myocardial perfusion reserve index. Spectral analysis of low-frequency to high-frequency ratio power during the Valsalva maneuver is associated with altered left ventricular torsion in subjects with T1DM. Parasympathetic dysfunction is closely associated with diastolic deficits. Cardiovascular autonomic neuropathy is not however the principal cause of impaired cardiac energetics. The role of CAN in the development of cardiomyopathy warrants further evaluation.     

Higher pulmonary dead space may predict prolonged mechanical ventilation after cardiac surgery

Children undergoing congenital heart surgery are at risk for prolonged mechanical ventilation and length of hospital stay. We investigated the prognostic value of pulmonary dead space fraction as a non‐invasive, physiologic marker in this population. In a prospective, cross‐sectional study, we measured pulmonary dead space fraction in 52 intubated, pediatric patients within 24 hr postoperative from congenital heart surgery. Measurements were obtained with a bedside, non‐invasive cardiac output (NICO) monitor (Respironics Novametrix, Inc., Wallingford, CT). Median pulmonary dead space fraction was 0.46 (25–75% IQR 0.34–0.55). Pulmonary dead space fraction significantly correlated with duration of mechanical ventilation and length of hospital stay in the entire cohort (r_s = 0.51, P = 0.0002; r_s = 0.51, P = 0.0002) and in the subset of patients without residual intracardiac shunting (r_s = 0.45, P = 0.008; r_s = 0.49, P = 0.004). In a multivariable logistic regression model, pulmonary dead space fraction remained an independent predictor for prolonged mechanical ventilation in the presence of cardiopulmonary bypass time and ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen (OR 2.2; 95% CI 1.14–4.38; P = 0.02). The area under the receiver operator characteristic curve for this model was 0.91. Elevated pulmonary dead space fraction is associated with prolonged mechanical ventilation and hospital stay in pediatric patients who undergo surgery for congenital heart disease and has additive predictive value in identifying those at risk for longer duration of mechanical ventilation. Pulmonary dead space may be a useful prognostic tool for clinicians in patients who undergo congenital heart surgery. Pediatr Pulmonol. 2009; 44:457–463. © 2009 Wiley‐Liss, Inc.     

Left ventricular structure and function in patients with rheumatoid arthritis,as assessed by cardiac magnetic resonance imaging

Objective

Heart failure is a major contributor to cardiovascular morbidity and mortality in patients with rheumatoid arthritis (RA), but little is known about myocardial structure and function in this population. This study was undertaken to assess the factors associated with progression to heart failure in patients with RA.

Methods

With the use of cardiac magnetic resonance imaging, measures of myocardial structure and function were assessed in men and women with RA enrolled in the Evaluation of Subclinical Cardiovascular Disease and Predictors of Events in Rheumatoid Arthritis study, a cohort study of subclinical cardiovascular disease in patients with RA, in comparison with non‐RA control subjects from a cohort enrolled in the Baltimore Multi‐Ethnic Study of Atherosclerosis.

Results

Measures of myocardial structure and function were compared between 75 patients with RA and 225 frequency‐matched controls. After adjustment for confounders, the mean left ventricular mass was found to be 26 gm lower in patients with RA compared with controls (P < 0.001), an 18% difference. In addition, the mean left ventricular ejection fraction, cardiac output, and stroke volume were modestly lower in the RA group compared with controls. The mean left ventricular end systolic and end diastolic volumes did not differ between the groups. In patients with RA, higher levels of anti–cyclic citrullinated peptide (anti‐CCP) antibodies and current use of biologic agents, but not other measures of disease activity or severity, were associated with significantly lower adjusted mean values for the left ventricular mass, end diastolic volume, and stroke volume, but not with ejection fraction. The combined associations of anti‐CCP antibody level and biologic agent use with myocardial measures were additive, without evidence of interaction.

Conclusion

These findings suggest that the progression to heart failure in RA may occur through reduced myocardial mass rather than hypertrophy. Both modifiable and nonmodifiable factors may contribute to lower levels of left ventricular mass and volume.

     

Effect of cardiac resynchronization therapy on libido and erectile dysfunction

Background:

Chronic heart failure (HF) is a common, complex clinical syndrome characterized by dyspnea, fatigue and exercise intolerance. HF patients experience decreased libido and erectile dysfunction (ED). The effects of cardiac resynchronization therapy (CRT) on libido and erectile function have not been previously evaluated. We aimed to investigate the effects of CRT on libido and ED.

Hypothesis:

Cardiac resynchronization therapy improves libido and ED.

Methods:

Thirty‐one male patients with advanced HF, scheduled for implantation of a CRT device, were included in the study. Left ventricular systolic function, New York Heart Association (NYHA) classs, libido, and ED were assessed before and 6 months after CRT. Libido and ED were evaluated with the Aging Male Symptoms (AMS) rating scale and internationally validated Sexual Health Inventory for Men (SHIM) questionnaire, respectively.

Results:

At the 6‐month follow‐up, the mean NYHA class improved from 3.4 ± 0.5 to 2.1 ± 0.6 (P<0.001). On echocardiographic examination, an improvement in left ventricular ejection fraction (LVEF) from 18 ± 5% to 32 ± 6% was detected (P<0.001). A significant increase in mean SHIM score and a significant decrease in mean AMS were noted. Changes in SHIM and AMS scores were correlated positively with the increase in LVEF (r = 0.47, P = 0.007 and r = ? 0.36, P = 0.04, respectively). Similarly, SHIM scores were correlated negatively (r = ? 0.57, P = 0.001) and AMS scores were correlated positively (r = 0.73, P = 0.0001) with the improvement in NYHA class.

Conclusions:

CRT results in a significant improvement in libido and erectile function in patients with congestive HF. This improvement is related to the improvements in the LVEF and functional capacity. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.