Effects of severity of long-standing congestive heart failure on pulmonary function

Prognostic Role of Pulmonary Function in Patients With Heart Failure With Reduced Ejection Fraction

Background

Both ventilatory abnormalities and pulmonary hypertension (PH) are frequently observed in patients with heart failure with reduced ejection fraction. We aim to investigate the association between ventilatory abnormalities and PH in heart failure with reduced ejection fraction, as well as their prognostic impacts.

Methods and Results

A total of 440 ambulatory patients (age, 66.2±15.8 years; 77% men) with left ventricular ejection fraction ≤40% who underwent comprehensive echocardiography and spirometry were enrolled. Total lung capacity, forced vital capacity, and forced expiratory volume in the first second were obtained. Pulmonary arterial systolic pressure was estimated. PH was defined as a pulmonary arterial systolic pressure of >50 mm Hg. The primary end point was all‐cause mortality at 5 years. Patients with PH had significantly reduced total lung capacity, forced vital capacity, and forced expiratory volume in the first second. During a median follow‐up of 25.9 months, there were 111 deaths. After accounting for age, sex, body mass index, renal function, smoking, left ventricular ejection fraction, and functional capacity, total lung capacity (hazard ratio [HR] per 1 SD, 0.66; 95% CI per 1 SD, 0.46–0.96), forced vital capacity (HR per 1 SD, 0.64; 95% CI per 1 SD, 0.48–0.84), and forced expiratory volume in the first second (HR per 1 SD, 0.72; 95% CI per 1 SD, 0.53–0.98) were all significantly correlated with mortality in patients without PH. Kaplan‐Meier curve demonstrated impaired pulmonary function, defined as forced expiratory volume in the first second ≤58% of predicted or forced vital capacity ≤65% of predicted, was associated with higher mortality in patients without PH (HR, 2.85; 95% CI, 1.66–4.89), but not in patients with PH (HR, 1.05; 95% CI, 0.61–1.82).

Conclusions

Ventilatory abnormality was more prevalent in patients with heart failure with reduced ejection fraction with PH than those without. However, such ventilatory defects were related to long‐term survival only in patients without PH, regardless of their functional status.

Pulmonary Function Testing Pre-heart Transplant Predicts Posttransplant Survival

Supplemental Digital Content is available in the text.

Although pulmonary function testing (PFT) is typically performed for heart transplant evaluation, the prognostic utility of PFTs after transplantation is unknown. We evaluated whether PFT parameters were correlated with outcomes following heart transplantation.

Misdiagnosis of Heart Failure: A Systematic Review of the Literature

BACKGROUND

Heart failure (HF) is a chronic disease associated with a significant burden to patients, families, and health services. The diagnosis of HF can be easily missed owing to similar symptoms with other conditions especially respiratory diseases.

METHODS AND RESULTS

We conducted a systematic review to determine the rates of HF and cardiomyopathy misdiagnosis and explored the potential causes. The included studies were narratively synthesized. Ten studies were identified including a total of 223,859 patients. There was a lack of definition of HF misdiagnosis in the studies and inconsistent diagnostic criteria were used. The rates of HF misdiagnosis ranged from 16.1% in hospital setting to 68.5% when general practitioner referred patients to specialist setting. The most common cause for misdiagnosis was chronic obstructive pulmonary disease (COPD). One study using a COPD cohort showed that HF was unrecognized in 20.5% of patients and 8.1% had misdiagnosis of HF as COPD. Another study suggests that anemia and chronic kidney disease are associated with an increase in the odds of unrecognized left ventricular systolic dysfunction. Other comorbidities such as obesity, old age, atrial fibrillation, and ischemic heart disease are prevalent in patients with a misdiagnosis of HF.

CONCLUSIONS

The misdiagnosis of HF is an unfortunate part of everyday clinical practice that occurs with a variable rate depending on the population studied. HF is frequently misdiagnosed as COPD. More research is needed to better understand the missed opportunities to correctly diagnose HF so that harm to patients can be avoided and effective treatments can be implemented.

Impact of chronic lung disease on quality-of-life outcomes in patients undergoing transcatheter aortic valve replacement

BACKGROUND

As the symptoms for both chronic lung disease (CLD) and aortic stenosis (AS) frequently overlap, it may be challenging to determine the degree of symptomatic improvement expected for a patient with CLD after correction of AS. Our aim was to determine if patients with CLD have the same degree of quality-of-life improvement following transcatheter aortic valve replacement (TAVR) as patients without CLD.

METHODS

A retrospective review of 238 TAVR patients from January 2017 to November 2018 who underwent preoperative pulmonary function tests and completed 30-day follow-up was performed. Patients were identified as having CLD with FEV1 more than 75% predicted. Postoperative outcomes and changes in Kansas City Cardiomyopathy Questionnaire-12 (KCCQ-12) were compared between groups.

RESULTS

Of the 238 patients identified, 143 (60.0%) had CLD, 50 (35.0%) of whom had an obstructive disease pattern. Patients with CLD were more likely to be male, had higher rates of peripheral artery disease, and had lower baseline ejection fraction. There was no difference in STS Predicted Risk of Mortality, but patients with CLD were more likely to be designated as high-risk by surgeon evaluation. While initial and follow-up KCCQ-12 was lower for patients with CLD, there was no significant difference in degree of improvement (p = .900). When comparing patients with obstructive lung disease (FEV1/FVC < 0.70) to those without CLD, there was also no significant difference in the change of quality of life (p = .720).

CONCLUSION

Although patients with concomitant severe AS and CLD have reduced baseline quality of life compared to patients without CLD, they experience a comparable degree of improvement following TAVR.

Association between the low percentage of forced vital capacity and increased mortality after left ventricular assist device implantation

Background

This study aims to investigate the effect of low percentage of forced vital capacity measured in the preoperative period on the 28-day mortality in patients undergoing left ventricular assist device implantation.

Methods

A total of 131 patients (111 males, 20 females; median age 54 years; range, 47 to 59 years) who underwent left ventricular assist device implantation with HeartWare™ between December 2010 and January 2016 were retrospectively analyzed. The patients were divided into two groups according to the results of pulmonary function test as a forced vital capacity percentage of ≥60% (n=113) and <60% (n=18). Both groups were compared in terms of laboratory and clinical characteristics, and postoperative complications. Risk factors for postoperative 28-day mortality were analyzed.

Results

Pre- and intraoperative characteristics were similar in both groups, except for left ventricular end-diastolic diameter. The ventilator-free days up to 28 days was shorter (p=0.046) and the length of intensive care unit stay was longer (p=0.011) in the low percentage of forced vital capacity group. The 28-day mortality rate was also higher (22.2% vs. 9.7%, respectively; p=0.12) in this group. The history of prior cardiac operation (odds ratio: 4.40; 95% confidence interval 1.19-16.20, p=0.026) and tricuspid valve repair at the time of device implantation (odds ratio: 5.30; 95% confidence interval 1.33-21.00, p=0.018) were found to be independent risk factors for mortality. Multivariate analysis showed that a forced vital capacity of <60% was not associated with mortality (odds ratio: 3.96; 95% confidence interval 0.95-16.43, p=0.058).

Conclusion

The length of intensive care unit stay and duration of mechanical ventilation may be longer in patients with a low percentage of forced vital capacity. Although the association between 28-day mortality and low percentage of forced vital capacity is not significant, the risk of 28-day mortality is higher in this group. Therefore, the patients should be assessed carefully before the left ventricular assist device operation.

Preoperative pulmonary function in all comers for cardiac surgery predicts mortality†

OBJECTIVES

Although reduced lung function and chronic obstructive pulmonary disease (COPD) is associated with higher risk of death following cardiac surgery, preoperative spirometry is not performed routinely. The aim of this study was to investigate the relationship between preoperative lung function and postoperative complications in all comers for cardiac surgery irrespective of smoking or COPD history.

METHODS

Preoperative spirometry was performed in elective adult cardiac surgery patients. Airflow obstruction was defined as the ratio of forced expiratory volume in 1 s (FEV1)/forced vital capacity ratio below the lower limit of normal (LLN) and reduced forced ventilatory capacity defined as FEV1 <LLN.

RESULTS

A history of COPD was reported by 132 (19%) patients; however, only 74 (56%) had spirometry-verified airflow obstruction. Conversely, 64 (12%) of the 551 patients not reporting a history of COPD had spirometry-verified airflow obstruction. The probability of death was significantly higher in patients with airflow obstruction (8.8% vs 4.5%, P = 0.04) and in patients with a FEV1 <LLN (8.7% vs 3.7%, P = 0.007). In the multivariate analysis were age [hazard ratio (HR) 1.6, 95% confidence interval (CI) 1.0-2.5; P = 0.04], prolonged cardiopulmonary bypass time (HR 1.2, 95% CI 1.02-1.3; P = 0.03), reduced kidney function (HR 2.5, 95% CI 1.2-5.6; P = 0.02) and FEV1 <LLN (HR 2.4, 95% CI 1.1-5.2; P = 0.03) all independently associated with an increased risk of death.

CONCLUSIONS

Preoperative spirometry reclassified 18% of the patients. A reduced FEV1 independently doubled the risk of death. Inclusion of preoperative spirometry in routine screening of cardiac surgical patients may improve risk prediction and identify high-risk patients.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01614951 (ClinicalTrials.gov).

The effect of diuresis on extravascular lung water and pulmonary function in acute decompensated heart failure

Aims

The effect of extravascular lung water (EVLW) and relationship to functional status as a result of acute decompensated heart failure (ADHF) are not well understood. We sought to quantify changes in clinical variables, EVLW, airway anatomy, spirometry, and diffusing capacity for carbon monoxide before and after treatment for ADHF.

Methods and results

Fifteen patients were recruited within 24 h of hospital admission. Spirometry, diffusing capacity for carbon monoxide, and surrogates of EVLW by computed tomography were measured and were then repeated within 24 h of discharge. From the computed tomography (CT) scan, surrogates of EVLW were calculated from the distribution of CT attenuation of the lung tissue. Airways were segmented using the vida apollo software. Patients were hospitalized for 4.6 ± 2.1 days, had 10 ± 4.8 L of fluid removed (7.0 ± 4.2 L between study visits), and lost 7.1 ± 4.9 kg. Patients had significant clearance of fluid from the lungs (per cent change: mean, 4.2 ± 6.1%; skew, 17.5 ± 27.0%; kurtosis, 37.6 ± 56.7%; full‐width half‐maximum, 10.2 ± 13.5%). Static lung volumes and maximal flows improved significantly (per cent change: forced vital capacity, 14.5 ± 13.6%; forced expiratory volume in 1 s, 15.9 ± 14.0%; forced expiratory flow at 25–75% of forced vital capacity, 27.2 ± 42.9%). The ratio of membrane conductance to capillary blood volume improved significantly (per cent change: alveolar–capillary membrane conductance/capillary blood volume, 23.4 ± 22.8%). Weight loss during hospitalization was significantly correlated with improved spirometry and diffusing capacity.

Conclusions

Extravascular lung water contributes to the pulmonary congestive syndrome in ADHF patients, and its clearance is an important component of the improvement in pulmonary function as a result of inpatient treatment.

Influence of Thoracic Fluid Compartments on Pulmonary Congestion in Chronic Heart Failure

INTRODUCTION

Pulmonary congestion is a common finding of heart failure (HF), but it remains unclear how pulmonary and heart blood volumes (V_p and V_h, respectively) and extravascular lung water (EVLW) change in stable HF and affect lung function.

METHODS

Fourteen patients with HF (age 68 ± 11 y, LVEF 33 ± 8%) and 12 control subjects (age 65 ± 9 y) were recruited. A pulmonary function test, thoracic computerized tomographic (CT) scan, and contrast perfusion scan were performed. From the thoracic scan, a histogram of CT attenuation of lung tissue was generated and skew, kurtosis, and full-width half-max (FWHM) calculated as surrogates of EVLW. Blood volumes were calculated from the transit time of the contrast through the great vessels of the heart.

RESULTS

Patients with HF had greater V_p and V_h (V_p 0.55 ± 0.21 L vs 0.41 ± 0.13 L; V_h 0.53 ± 0.33 L vs 0.40 ± 0.15 L) and EVLW (skew 3.2 ± 0.5 vs 3.7 ± 0.7; kurtosis 19.4 ± 6.6 vs 25.9 ± 9.4; FWHM 73 ± 13 HU vs 59 ± 9 HU). Spirometric measures were decreased in HF (percentage of predicted: forced vital capacity 86 ± 17% vs 104 ± 9%; forced expiratory volume in 1 second 83 ± 20% vs 105 ± 11%; maximal mid-expiratory flow 82 ± 42% vs 115 ± 43%). V_p was associated with decreased expiratory flows, and EVLW was associated with decreased lung volumes.

CONCLUSIONS

Congestion in stable patients with HF includes expanded V_p and V_h and increased EVLW associated with reductions in lung volumes and expiratory flows.

Influence of heart failure on resting lung volumes in patients with COPD

Objective:

To evaluate the influence of chronic heart failure (CHF) on resting lung volumes in patients with COPD, i.e., inspiratory fraction-inspiratory capacity (IC)/TLC-and relative inspiratory reserve-[1 − (end-inspiratory lung volume/TLC)].

Methods:

This was a prospective study involving 56 patients with COPD-24 (23 males/1 female) with COPD+CHF and 32 (28 males/4 females) with COPD only-who, after careful clinical stabilization, underwent spirometry (with forced and slow maneuvers) and whole-body plethysmography.

Results:

Although FEV₁, as well as the FEV₁/FVC and FEV₁/slow vital capacity ratios, were higher in the COPD+CHF group than in the COPD group, all major "static" volumes-RV, functional residual capacity (FRC), and TLC-were lower in the former group (p < 0.05). There was a greater reduction in FRC than in RV, resulting in the expiratory reserve volume being lower in the COPD+CHF group than in the COPD group. There were relatively proportional reductions in FRC and TLC in the two groups; therefore, IC was also comparable. Consequently, the inspiratory fraction was higher in the COPD+CHF group than in the COPD group (0.42 ± 0.10 vs. 0.36 ± 0.10; p < 0.05). Although the tidal volume/IC ratio was higher in the COPD+CHF group, the relative inspiratory reserve was remarkably similar between the two groups (0.35 ± 0.09 vs. 0.44 ± 0.14; p < 0.05).

Conclusions:

Despite the restrictive effects of CHF, patients with COPD+CHF have relatively higher inspiratory limits (a greater inspiratory fraction). However, those patients use only a part of those limits, probably in order to avoid critical reductions in inspiratory reserve and increases in elastic recoil.

Prevalence of airflow obstruction in patients with stable systolic heart failure

Background

Chronic obstructive pulmonary disease (COPD) is an important differential diagnosis in heart failure (HF). However, routine use of spirometry in outpatient HF clinics is not implemented. The aim of the present study was to determine the prevalence of both airflow obstruction and non obstructive lung function impairment in patients with HF and to examine the effect of optimal medical treatment for HF on lung function parameters.

Methods

Consecutive patients with HF (ejection fraction (EF) < 45%) and New York Heart Association (NYHA) functional class II-IV at 10 different outpatient heart failure clinics were examined with spirometry at their first visit and after optimal medical treatment for HF was achieved. airflow obstruction was classified and graded according to the GOLD 2011 revision.

Results

Baseline spirometry was performed in 593 included patients and 71 (12%) had a clinical diagnosis of COPD. Mean age was 69 ± 11 years and mean EF was 30 ± 9%. Thirty-two % of the patients were active smokers and 53% were previous smokers. Mean FEV₁ and FVC was 77.9 ± 1.7% and 85.4 ± 1.5% of predicted respectively. Obstructive pattern was observed in 233 (39%) of the patients. Of these, 53 patients (9%) had mild disease (GOLD I) and 180 (30%) patients had moderate to very severe disease (GOLD II-IV). No difference in spirometric variables was observed following up titration of medication.

Conclusion

In stable patients with HF airflow obstruction is frequent and severely underdiagnosed. Spirometry should be considered in all patients with HF in order to improve diagnosis and treatment for concomitant pulmonary disease.

Comorbidities in Heart Failure

Comorbidities frequently accompany chronic heart failure (HF), contributing to increased morbidity and mortality, and an impaired quality of life. We describe the prevalence of several high-impact comorbidities in chronic HF patients and their impact on morbidity and mortality. Furthermore, we try to explain the underlying pathophysiological processes and the complex interaction between chronic HF and specific comorbidities. Although common risk factors are likely to contribute, it is reasonable to believe that factors associated with HF might cause other comorbidities and vice versa. Potential factors are inflammation, neurohormonal activation, and hemodynamic changes.

Challenges in the Management of Patients with Chronic Obstructive Pulmonary Disease and Heart Failure With Reduced Ejection Fraction

Chronic obstructive pulmonary disease (COPD) and heart failure with reduced ejection fraction (HFrEF) commonly coexist in clinical practice. The prevalence of COPD among HFrEF patients ranges from 20 to 32 %. On the other hand; HFrEF is prevalent in more than 20 % of COPD patients. With an aging population, the number of patients with coexisting COPD and HFrEF is on rise. Coexisting COPD and HFrEF presents a unique diagnostic and therapeutic clinical conundrum. Common symptoms shared by both conditions mask the early referral and detection of the other. Beta blockers (BB), angiotensin-converting enzyme inhibitors, and aldosterone antagonists have been shown to reduce hospitalizations, morbidity, and mortality in HFrEF while long-acting inhaled bronchodilators (beta-2-agonists and anticholinergics) and corticosteroids have been endorsed for COPD treatment. The opposing pharmacotherapy of BBs and beta-2-agonists highlight the conflict in prescribing BBs in COPD and beta-2-agonists in HFrEF. This has resulted in underutilization of evidence-based therapy for HFrEF in COPD patients owing to fear of adverse effects. This review aims to provide an update and current perspective on diagnostic and therapeutic management of patients with coexisting COPD and HFrEF.

Impact of chronic systolic heart failure on lung structure-function relationships in large airways

Heart failure (HF) is often associated with pulmonary congestion, reduced lung function, abnormal gas exchange, and dyspnea. We tested whether pulmonary congestion is associated with expanded vascular beds or an actual increase in extravascular lung water (EVLW) and how airway caliber is affected in stable HF. Subsequently we assessed the influence of an inhaled short acting beta agonist (SABA). Thirty‐one HF (7F; age, 62 ± 11 years; ht. 175 ± 9 cm; wt. 91 ± 17 kg; LVEF, 28 ± 15%) and 29 controls (11F; age; 56 ± 11 years; ht. 174 ± 8 cm; wt. 77 ± 14 kg) completed the study. Subjects performed PFTs and a chest computed tomography (CT) scan before and after SABA. CT measures of attenuation, skew, and kurtosis were obtained from areas of lung tissue to assess EVLW. Airway luminal areas and wall thicknesses were also measured. CT tissue density suggested increased EVLW in HF without differences in the ratio of airway wall thickness to luminal area or luminal area to TLC (skew: 2.85 ± 1.08 vs. 2.11 ± 0.79, P < 0.01; Kurtosis: 15.5 ± 9.5 vs. 9.3 ± 5.5 P < 0.01; control vs. HF). PFTs were decreased in HF at baseline (% predicted FVC:101 ± 15% vs. 83 ± 18%, P < 0.01;FEV1:103 ± 15% vs. 82 ± 19%, P < 0.01;FEF25–75: 118 ± 36% vs. 86 ± 36%, P < 0.01; control vs. HF). Airway luminal areas, but not CT measures, were correlated with PFTs at baseline. The SABA cleared EVLW and decreased airway wall thickness but did not change luminal area. Patients with HF had evidence of increased EVLW, but not an expanded bronchial circulation. Airway caliber was maintained relative to controls, despite reductions in lung volume and flow rates. SABA improved lung function, primarily by reducing EVLW.

Reversible decline in pulmonary function during left ventricular assist device therapy

Cardiac replacement therapy, consisting of left ventricular assist device (LVAD) implant surgery and heart transplantation, has considerably reduced the mortality and morbidity of patients with stage D heart failure. However, its impact on pulmonary function remains unclear. We retrospectively evaluated 22 consecutive patients (16 men; 42 ± 13 years old) who had undergone pulmonary function tests during the heart failure, LVAD, and heart transplantation periods. The LVAD therapy lasted an average of 871 ± 267 days. The % vital capacity and forced expiratory volume in 1 s decreased significantly after LVAD implantation and returned to baseline levels after heart transplantation. Correlation analysis indicated that a shorter duration of LVAD support was associated with a more significant improvement in % vital capacity in heart transplantation recipients, compared to the pre-LVAD period and the LVAD period. In conclusion, we provide evidence that a decrease in pulmonary function occurs during LVAD support but it may be reversible. Limited LVAD duration may be a key for the recovery of pulmonary dysfunction.

COPD in patients with stable heart failure in the primary care setting

BACKGROUND

Presence of chronic obstructive pulmonary disease (COPD) in heart failure (HF) has prognostic and therapeutic implications. Exact prevalence estimates are lacking because most previous studies estimated the prevalence of COPD among HF patients while unstable and in the presence of pulmonary congestion.

METHODS

Community-dwelling patients with an established diagnosis of HF and in a stable phase of their disease were invited for spirometry. COPD was defined according to the Global initiative for chronic Obstructive Lung Disease (GOLD) classification and considered present if the ratio of the post-bronchodilator forced expiratory volume in 1 second and forced vital capacity was below 0.7.

RESULTS

Thirty of the 106 patients with HF (mean age 76 [standard deviation] 11.9 years, 57% male) had COPD (prevalence 28.3% [95% confidence interval (CI) 19.7%-36.9%]), with similar rates among those with HF and a reduced ejection fraction (18 individuals; prevalence 28.6% [95% CI 20.0%-37.2%]) and HF with preserved ejection fraction (12 individuals; prevalence 27.9% [95% CI 19.4-36.4]). Twenty-one (70%) of the 30 participants were newly detected cases of COPD.

CONCLUSION

More than a quarter of the patients with HF concomitantly have COPD, with the large majority being previously unrecognized. Coexistence of COPD should be considered more often in these patients.

Changes in Spirometry After Left Ventricular Assist Device Implantation

Left ventricular assist devices (LVADs) are increasingly being used as life-saving therapy in patients with end-stage heart failure. The changes in spirometry following LVAD implantation and subsequent unloading of the left ventricle and pulmonary circulation are unknown. In this study, we explored long-term changes in spirometry after LVAD placement. In this retrospective study, we compared baseline preoperative pulmonary function test (PFT) results to post-LVAD spirometric measurements. Our results indicated that pulmonary function tests were significantly reduced after LVAD placement (forced expiratory volume in one second [FEV1 ]: 1.9 vs.1.7, P = 0.016; forced vital capacity [FVC]: 2.61 vs. 2.38, P = 0.03; diffusing capacity of the lungs for carbon monoxide [DLCO]: 14.75 vs. 11.01, P = 0.01). Subgroup analysis revealed greater impairment in lung function in patients receiving HeartMate II (Thoratec, Pleasanton, CA, USA) LVADs compared with those receiving HeartWare (HeartWare, Framingham, MA, USA) devices. These unexpected findings may result from restriction of left anterior hemi-diaphragm; however, further prospective studies to validate our findings are warranted.

Beneficial Effects of Positive Airway Pressure Therapy for Sleep-Disordered Breathing in Heart Failure Patients With Preserved Left Ventricular Ejection Fraction

BACKGROUND

Right-heart dysfunction is associated with poor prognosis in heart failure with preserved left ventricular ejection fraction (HFpEF). It remains unclear whether sleep-disordered breathing (SDB) treatment using positive airway pressure (PAP) improves right-heart and pulmonary function and exercise capacity and reduces mortality rates of HFpEF patients.

HYPOTHESIS

PAP may improve right-heart and pulmonary function, exercise capacity and prognosis in HFpEF patients with SDB.

METHODS

One hundred nine consecutive patients with HFpEF (left ventricular ejection fraction >50%) and moderate to severe SDB (apnea-hypopnea index ≥15/h) treated with medications were divided into 2 groups: 31 patients with PAP (PAP group) and 78 patients without PAP (non-PAP group). Right ventricular fractional area change (RV-FAC), tricuspid valve regurgitation pressure gradient (TR-PG), tricuspid valve E/E', forced expiratory volume in 1 second/forced vital capacity (FEV1 /FVC), percentage of vital capacity, and peak VO2 were determined before and 6 months later, and all-cause mortality was followed up for 916 days.

RESULTS

All parameters improved in the PAP group (RV-FAC, 36.0% -46.5%; TR-PG, 31.1 mm Hg-22.4 mm Hg; tricuspid valve E/E', 7.8-5.1; FEV1 /FVC, 83.9%-89.8%; percentage of vital capacity, 83.5%-89.9%; and peak VO2 , 16.6 mL/kg/min-19.6 mL/kg/min; P <0.05, respectively) but not in the non-PAP group. Importantly, all-cause mortality was significantly lower in the PAP group than in the non-PAP group (0% vs 12.8%; log-rank P = 0.014).

CONCLUSIONS

Positive airway pressure improves right-heart and pulmonary function and exercise capacity and may reduce all-cause mortality in patients with HFpEF and SDB.

Co-morbidities in heart failure

Heart failure is a clinical syndrome characterized by poor quality of life and high morbidity and mortality. Co-morbidities frequently accompany heart failure and further decrease in both quality of life and clinical outcome. We describe that the prevalence of co-morbidities in patients with heart failure is much higher compared to age-matched controls. We will specifically address the most studied organ-related co-morbidities, that is, renal dysfunction, cerebral dysfunction, anaemia, liver dysfunction, chronic obstructive pulmonary disease, diabetes mellitus and sleep apnoea. The pathophysiologic processes underlying the interaction between heart failure and co-morbid conditions are complex and remain largely unresolved. Although common risk factors are likely to contribute, it is reasonable to believe that factors associated with heart failure might cause other co-morbid conditions. Inflammation, neurohumoral pathway activation and hemodynamic changes are potential factors. We try to provide explanations for the observed association between co-morbidities and heart failure, as well as its impact on survival.

Lung capillary injury and repair in left heart disease: a new target for therapy?

The lungs are the primary organs affected in LHD (left heart disease). Increased left atrial pressure leads to pulmonary alveolar–capillary stress failure, resulting in cycles of alveolar wall injury and repair. The reparative process causes the proliferation of MYFs (myofibroblasts) with fibrosis and extracellular matrix deposition, resulting in thickening of the alveolar wall. Although the resultant reduction in vascular permeability is initially protective against pulmonary oedema, the process becomes maladaptive causing a restrictive lung syndrome with impaired gas exchange. This pathological process may also contribute to PH (pulmonary hypertension) due to LHD. Few clinical trials have specifically evaluated lung structural remodelling and the effect of related therapies in LHD. Currently approved treatment for chronic HF (heart failure) may have direct beneficial effects on lung structural remodelling. In the future, novel therapies specifically targeting the remodelling processes may potentially be utilized. In the present review, we summarize data supporting the clinical importance and pathophysiological mechanisms of lung structural remodelling in LHD and propose that this pathophysiological process should be explored further in pre-clinical studies and future therapeutic trials.

Prognostic value of resting pulmonary function in heart failure

BACKGROUND

The heart and lungs are intimately linked anatomically and physiologically, and, as a result, heart failure (HF) patients often develop changes in pulmonary function. This study examined the prognostic value of resting pulmonary function (PF) in HF.

METHODS AND RESULTS

In all, 134 HF patients (enrolled from January 1, 1999 Through December 31, 2005; ejection fraction (EF) = 29% ± 11%; mean age = 55 ± 12 years; 65% male) were followed for 67 ± 34 months with death/transplant confirmed via the Social Security Index and Mayo Clinic registry. PF included forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), diffusing capacity of the lungs for carbon monoxide (DLCO), and alveolar volume (VA). Patients were divided in tertiles according to PF with survival analysis via log-rank Mantel-Cox test with chi-square analysis. Groups for FVC included (1) >96%, (2) 96% to 81%, and (3) <81% predicted (chi-square = 18.9, P < 0.001). Bonferroni correction for multiple comparisons (BC) suggested differences between groups 1 and 3 (P < 0.001) and 2 and 3 (P = 0.008). Groups for FEV1 included (1) >94%, (2) 94% to 77%, and (3) <77% predicted (chi-square = 17.3, P <0.001). BC suggested differences between groups 1 and 3 (P <0.001). Groups for DLCO included (1) >90%, (2) 90% to 75%, and (3) <75% predicted (chi-square = 11.9, P = 0.003). BC suggested differences between groups 1 and 3 (P < 0.001). Groups for VA included (1) >97%, (2) 97% to 87%, and (3) <87% predicted (Chi-square = 8.5, P = 0.01). BC suggested differences between groups 1 and 2 (P = 0.014) and 1 and 3 (P = 0.003).

CONCLUSIONS

In a well-defined cohort of HF patients, resting measures of PF are predictive of all-cause mortality.

Forced expiratory volume in one second predicts length of stay and in-hospital mortality in patients undergoing cardiac surgery: a retrospective cohort study

Objective

An aging population and increasing use of percutaneous therapies have resulted in older patients with more co-morbidity being referred for cardiac surgery. Objective measurements of physiological reserve and severity of co-morbid disease are required to improve risk stratification. We hypothesised that FEV₁ would predict mortality and length of stay following cardiac surgery.

Methods

We assessed clinical outcomes in 2,241 consecutive patients undergoing coronary artery bypass grafting and/or valve surgery from 2001 to 2007 in a regional cardiac centre. Generalized linear models of the association between FEV₁ and length of hospital stay and mortality were adjusted for age, sex, height, body mass index, socioeconomic status, smoking, cardiovascular risk factors, long-term use of bronchodilators or steroids for lung disease, and type and urgency of surgery. FEV₁ was compared to an established risk prediction model, the EuroSCORE.

Results

Spirometry was performed in 2,082 patients (93%) whose mean (SD) age was 67 (10) years. Median hospital stay was 3 days longer in patients in the lowest compared to the highest quintile for FEV₁, 1.35-fold higher (95% CI 1.20–1.52; p<0.001). The adjusted odds ratio for mortality was increased 2.11-fold (95% CI 1.45–3.08; p<0.001) per standard deviation decrement in FEV₁ (800 ml). FEV₁ improved discrimination of the EuroSCORE for mortality. Similar associations were found after excluding people with known pulmonary disease and/or airflow limitation on spirometry.

Conclusions

Reduced FEV₁ strongly predicted increased length of stay and in-hospital mortality following cardiac surgery. FEV₁ is a widely available measure of physiological health that may improve risk stratification of complex patients undergoing cardiac surgery and should be evaluated for inclusion in new prediction tools.

Airway obstruction in systolic heart failure--COPD or congestion?

BACKGROUND

The diagnosis of chronic obstructive pulmonary disease (COPD) in patients with systolic heart failure (SHF) is challenging because symptoms of both conditions overlap. We aimed to estimate the prevalence, correlates and prognostic impact of true COPD in patients with SHF.

METHODS

To diagnose COPD under stable conditions according to the guidelines, pulmonary function testing (PFT) was performed in 619 patients six months after hospitalization for congestive SHF. In 272 patients, PFT had been also performed prior to discharge.

RESULTS

In the total cohort, COPD was reported in 23% (144/619). PFT under stable conditions revealed that COPD was absent in 73% (449/619), unconfirmed in 18% (112/619), and proven in 9% (58/619). In 272 patients with serial PFT, initial airway obstruction was found in 19% (51/272) but had resolved in 47% of those (24/51) after six months. Initial hyperinflation detected by bodyplethysmography strongly predicted proven COPD six months later: odds ratio for elevated intrathoracic gas volume 12.8, 95% confidence interval (CI) 2.5-65.9; p=0.002. After a median follow-up of 34 months, 27% of the total cohort (165/619) had died. Only proven COPD was associated with an increased mortality risk after adjustment for age, sex, NYHA functional class, ejection fraction, atrial fibrillation, smoking, renal dysfunction and diabetes: hazard ratio 1.64, 95%CI 1.03-2.63; p=0.039.

CONCLUSIONS

Airway obstruction is a dynamic phenomenon in SHF. Therefore, a valid diagnosis of COPD in SHF demands serial PFT under stable conditions with special attention to hyperinflation. COPD proven by PFT is associated with an increased all-cause mortality risk.

Cardiac asthma

Cardiac dyspnea, especially if present only with exercise, is often confused with asthma and exercise-induced bronchospasm. Cardiac dyspnea or asthma is the consequence of pulmonary edema due to pulmonary venous hypertension and not due to asthmatic bronchoconstriction. In overt, acute congestive heart failure, the diagnosis may be readily made by history and physical examination and pertinent laboratory and imaging data.

The comorbidity conundrum: a focus on the role of noncardiovascular chronic conditions in the heart failure patient

The rapid aging of the US population combined with improvements in modern medicine has created a new public health concern of comorbidity, a chronic condition that co-exists with a primary illness. Over 141 million Americans suffer from one or more comorbid conditions. In the heart failure (HF) patient, this comorbidity burden is particularly high, with over 40% of patients having five or more chronic conditions. These comorbidities can vary from being a risk factor to a cause of HF progression or even a precipitating factor for decompensation. Comorbidities, particularly the noncardiovascular conditions, have been associated with greater health resource utilization, poor health outcomes, and increased mortality. To minimize the negative impact that these comorbidities have on patient outcomes, appropriate attention should be paid to identifying, prioritizing, and managing each condition; minimizing medication complexity and polypharmacy; and improving overall coordination of care between providers and patients.

The impact of heart failure on the classification of COPD severity

BACKGROUND

Pulmonary restriction-a reduction of lung volumes-is common in heart failure (HF), rendering severity grading of chronic obstructive pulmonary disease (COPD) potentially problematic in subjects with both diseases. We compared pulmonary function in patients with either HF or COPD, or the combination to assess whether grading of COPD using the Global Initiative of Chronic Obstructive Lung Disease classification is hampered in the presence of HF.

METHODS AND RESULTS

In 2 cohorts involving 591 patients with established HF and 405 with a primary care diagnosis of COPD, the presence of HF and COPD was assessed according to guidelines. HF severity was staged according to the NYHA classification system into Classes I-IV. COPD was diagnosed if the ratio of post-bronchodilator forced expiratory volume in 1 second and forced vital capacity (FEV1/FVC) was <0.70, and categorized in GOLD stages I-IV according to post-bronchodilator-predicted FEV1 levels (FEV1% ≥80%; 50-79%; 30-49%; <30%). In total, 557 patients with HF only, 108 with HF+COPD, and 194 with COPD only were studied. Patients, who had neither HF nor COPD according to definition, or HF with reversible obstruction in post-bronchodilator pulmonary function tests were excluded from this analysis (n = 137). Compared with COPD only, patients with HF plus COPD had higher levels of post-bronchodilator FEV1/FVC (median [quartiles] 0.57 [0.47-0.64] vs 0.62 [0.55-0.66] and lower total lung capacity % (115 [104-126]% vs 105 [95-117]%, P < .001) P < .001), but comparable levels of post-bronchodilator FEV1% (70 [56-84]% vs 68 [54-80]%, P = .22) and thus similar distributions of GOLD stages I-IV in both groups (24/56/19/4% vs 31/50/19/1%, P = .57). In patients with HF only, 25% exhibited pre-bronchodilator FEV1% levels of <80% (FEV1% 94 [80-108]%), despite a pre-bronchodilator FEV/FVC ratio ≥0.7 in this group. The reduction of FEV1 in patients with HF only was associated with HF severity.

CONCLUSIONS

In stable HF, FEV1 may be significantly reduced even in the absence of "real" airflow obstruction. In this situation, diagnosing COPD according to GOLD criteria (based on FEV1/FVC) still seems feasible, because both FEV1 and FVC are usually decreased to an equal extent in HF. However, classifying COPD based on FEV1 levels may overrate obstruction severity in patients with combined disease (HF plus COPD), and thus may lead to unjustified use of bronchodilators.

Comparison between ATS/ERS age- and gender-adjusted criteria and GOLD criteria for the detection of irreversible airway obstruction in chronic heart failure

BACKGROUND

Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria (FEV1/FVC <70%) are extensively used for diagnosis of chronic obstructive lung disease in heart failure (HF). The American Thoracic Society (ATS)/European Respiratory Society (ERS) recommends the use of age- and gender-specific lower limit of normal (LLN) for FEV1/FVC. We compared the impact of these definitions on apparent prevalence of airway obstruction in chronic HF.

METHODS

Standardized pre- and post-bronchodilator spirometry was performed in HF patients. Airway obstruction was defined by ATS/ERS criteria as diagnostic standard. Additionally, airway obstruction was calculated using the GOLD criteria.

RESULTS

Of the 89 participants who fulfilled the ATS criteria for acceptability and reproducibility, 24.7% met ATS/ERS and 43.8% GOLD criteria for airway obstruction (Chi-square p = 0.007, McNemar <0.001). Sensitivity of GOLD criteria was 100%, specificity 74.6%, positive predictive value 56.4% and negative predictive value 100%. Among all individuals with an FEV1/FVC > LLN, 25.4% were falsely identified when using the GOLD criteria. A majority of false positives qualified for airway obstruction GOLD stage I (FEV1% ≥80%), which was significantly less often observed among true positives (76.5 vs. 31.8%; p < 0.001). Only 31.8% of patients with irreversible airway obstruction detected by the ATS/ERS criteria reported a history of COPD.

CONCLUSIONS

In all HF patients with persistent dyspnoea despite optimal HF treatment, spirometric testing should be performed. Application of the GOLD criteria leads to overdiagnosis of irreversible airway obstruction in patients with HF, which may result in inappropriate medical therapy and health-care decisions.

Role of aldosterone on lung structural remodelling and right ventricular function in congestive heart failure

Background

The mechanisms of benefit of mineralocorticoid receptors antagonists in congestive heart failure (CHF) are still debated. We hypothesized that aldosterone contributes to pulmonary remodelling and right ventricular (RV) dysfunction associated with CHF by stimulation of lung myofibroblasts (MYFs) proliferation.

Methods

Rats with moderate to large myocardial infarcts (MI) and CHF were studied. Two weeks after MI, spironolactone 100 mg/kg/day (n = 21) or no treatment (n = 24) were given for 3 weeks and compared to sham (n = 8).

Results

Infarct size was similar by ultrasound and pathologic measures in both MI groups.

The MI-untreated group developed important lung remodelling with nearly doubling of dry lung weight (p < 0.01), reduced left ventricular (LV) fractional shortening (16 ± 2% vs. 53 ± 1%; mean ± SEM, p < 0.0001), pulmonary hypertension (RV systolic pressure: 40 ± 3 mmHg vs. 27 ± 1 mmHg, p < 0.01) and RV hypertrophy (RV/(LV + septum): 38 ± 3% vs. 24 ± 1%, p < 0.05). Spironolactone had no effect on these parameters and did not improve LV or RV performance (tricuspid annular plane systolic excursion and RV myocardial performance index) measured by echocardiography. CHF induced a restrictive respiratory syndrome with histological lung fibrosis: this was also unaffected by spironolactone. Finally, isolated lung MYFs did not proliferate after exposure to aldosterone.

Conclusion

Aldosterone does not significantly contribute to pulmonary remodelling and RV dysfunction associated with CHF. Other mechanisms are responsible for the beneficial effects of spironolactone in CHF.

The resistive and elastic work of breathing during exercise in patients with chronic heart failure

Patients with heart failure (HF) display numerous derangements in ventilatory function, which together serve to increase the work of breathing (W(b)) during exercise. However, the extent to which the resistive and elastic properties of the respiratory system contribute to the higher W(b) in these patients is unknown. We quantified the resistive and elastic W(b) in patients with stable HF (n = 9; New York Heart Association functional class I-II) and healthy control subjects (n = 9) at standardised levels of minute ventilation (V'(E)) during graded exercise. Dynamic lung compliance was systematically lower for a given level of V'(E) in HF patients than controls (p<0.05). HF patients displayed slightly higher levels of inspiratory elastic W(b) with greater amounts of ventilatory constraint and resistive W(b) than control subjects during exercise (p<0.05). Our data indicates that the higher W(b) in HF patients is primarily due to a greater resistive, rather than elastic, load to breathing. The greater resistive W(b) in these patients probably reflects an increased hysteresivity of the airways and lung tissues. The marginally higher inspiratory elastic W(b) observed in HF patients appears related to a combined decrease in the compliances of the lungs and chest wall. The clinical and physiological implications of our findings are discussed.

Repercussões da cardiomegalia na função pulmonar de indivíduos adultos com insuficiência cardíaca crônica: uma revisão sistemática

Para analisar as repercussões da cardiomegalia sobre a função pulmonar em indivíduos adultos com insuficiência cardíaca (IC) crônica, foram revisados artigos nas bases PUBMED, BIREME, ISI Web of Knowledge e COCHRANE, publicados na última década, estudos observacionais e sem restrição de idioma. Utilizados os descritores "cardiomegaly" e "Respiratory Function Tests", e negada a palavra "exercise". Foram incluídos artigos com IC crônica, de ambos os sexos, entre 19 e 64 anos, incluindo IC congestiva e cardiomiopatia dilatada e excluídos com IC aguda, com avaliações pós-intervenção clínica ou por exercício. Para avaliar a qualidade dos artigos foi utilizada a escala da Agency for Healthcare Research and Quality (AHRQ) e aceitos aqueles com escore>50 pontos (0-100). Foram selecionados cinco artigos do total de 1093 e agrupados por parâmetros relacionados aos fluxos e volumes pulmonares, padrão ventilatório e desempenho muscular. Na AHRQ, dois estudos ficaram na faixa de 50-75% e os demais >75%. Eles apontam para redução da capacidade vital inspiratória (CVI), volume expiratório forçado no 1º segundo (VEF1) e pressão inspiratória máxima (PImáx) em função da cardiomegalia, com discreta redução na relação VEF1/CVI e na capacidade de difusão para monóxido de carbono (DLCO). Portanto, segundo os estudos, a cardiomegalia leva a um padrão respiratório restritivo, com redução do volume alveolar que interfere na DLCO. As correlações mais fortes envolvem a redução da PImáx, CVI e VEF1.

Heart failure and the lung

Heart failure (HF) is a highly prevalent disease that leads to significant morbidity and mortality. There is increasing evidence that the symptoms of HF are exacerbated by its deleterious effects on lung function. HF appears to cause airway obstruction acutely and leads to impaired gas diffusing capacity and pulmonary hypertension in the longer term. It is postulated that this is the result of recurrent episodes of elevated pulmonary capillary pressure leading to pulmonary oedema and pulmonary capillary stress fracture, which produces lung fibrosis. It is likely that impaired lung function impairs the functional status of HF patients and makes them more prone to central sleep apnoea.

Influence of cardiomegaly on disordered breathing during exercise in chronic heart failure

AIMS

Heart failure (HF) patients breathe with a rapid shallow pattern during exercise. This study examined the relationship between cardiac size and tachypnoeic breathing in HF patients during exercise.

METHODS AND RESULTS

Thirty-seven HF patients [age = 55 ± 13 years, ejection fraction (EF) = 27 ± 10%, New York Heart Association (NYHA) class = 2.3 ± 1.2] and 42 controls (CTL) (age = 56 ± 14 years, EF = 63 ± 8%) were recruited. Participants underwent maximal exercise testing, pulmonary function testing, and chest radiography for calculation of total thoracic cavity volume (TTCV), diaphragm, heart, and lung volumes. Heart failure patients were divided into two groups: Group A = cardiac volume < median (n = 18) and Group B = cardiac volume ≥ median of the HF patients (n = 19). There was no difference between groups for TTCV (CTL = 8203 ± 1489 vs. Group A = 8694 ± 1249 vs. Group B = 8195 ± 1823 cm(3)). Cardiac volume was different between groups for both absolute (CTL = 630 ± 181 vs. Group A = 894 ± 186 vs. Group B = 1401 ± 382 cm(3), P< 0.001 for all comparisons) and %TTCV (CTL = 8 ± 2 vs. Group A = 10 ± 1 vs. Group A = 18 ± 5%, P< 0.001 for all comparisons). Similarly, total lung volume as a %TTCV was significantly different among the groups (CTL = 70 ± 4 vs. Group A = 65 ± 5 vs. Group A = 58 ± 7%, P< 0.01 for all comparisons). In HF patients, there was a trend (P = 0.10) towards an independent association between cardiac size and tidal volume (V(T)) at 75% of VO(2) peak whereas this relationship was statistically significant at VO(2) peak (P = 0.02) as patients with larger cardiac size had reduced V(T).

CONCLUSION

This study demonstrates the close relationship between cardiac size and breathing pattern during exercise in HF patients. These results suggest cardiac size may pose a significant constraint on the lungs during exercise and may contribute to tachypnoeic breathing.

Effects of respiratory muscle work on blood flow distribution during exercise in heart failure

Heart failure (HF) patients have a reduced cardiac reserve and increased work of breathing. Increased locomotor muscle blood flow demand may result in competition between respiratory and locomotor vascular beds. We hypothesized that HF patients would demonstrate improved locomotor blood flow with respiratory muscle unloading during activity. Ten patients (ejection fraction = 31 +/- 3%) and 10 controls (CTL) underwent two cycling sessions (60% peak work). Session 1 (S1): 5 min of normal breathing (NB), 5 min respiratory muscle unloading with a ventilator, and 5 min of NB. Session 2 (S2): 5 min NB, 5 min of respiratory muscle loading with inspiratory resistance, and 5 min of NB. Measurements included: leg blood flow (LBF, thermodilution), cardiac output (Q), and oesophageal pressure (P(pl), index of pleural pressure). S1: P(pl) was reduced in both groups (HF: 73 +/- 8%; CTL: 60 +/- 13%, P < 0.01). HF: Q increased (9.6 +/- 0.4 vs. 11.3 +/- 0.8 l min(-1), P < 0.05) and LBF increased (4.8 +/- 0.8 vs. 7.3 +/- 1.1 l min(-1), P < 0.01); CTL: no changes in Q (14.7 +/- 1.0 vs. 14.8 +/- 1.6 l min(-1)) or LBF (10.9 +/- 1.8 vs. 10.3 +/- 1.7 l min(-1)). S2: P(pl) increased in both groups (HF: 172 +/- 16%, CTL: 220 +/- 40%, P < 0.01). HF: no change was observed in Q(10.0 +/- 0.4 vs. 10.3 +/- 0.8 l min(-1)) or LBF (5.0 +/- 0.6 vs. 4.7 +/- 0.5 l min(-1)); CTL: increased (15.4 +/- 1.4 vs. 16.9 +/- 1.5 l min(-1), P < 0.01) and LBF remained unchanged (10.7 +/- 1.5 vs. 10.3 +/- 1.8 l min(-1)). These data suggest HF patients preferentially steal blood flow from locomotor muscles to accommodate the work of breathing during activity. Further, HF patients are unable to vasoconstrict locomotor vascular beds beyond NB when presented with a respiratory load.

Mortality after an Emergency Department Visit for Exacerbation of Chronic Obstructive Pulmonary Disease

OBJECTIVE

To describe the mortality after emergency department (ED) visits for chronic obstructive pulmonary disease (COPD) exacerbation.

DESIGN

Retrospective cohort study of ED patients with COPD exacerbation. Setting. Administrative data analysis.

PARTICIPANTS

Patients age 55 and over who visited the ED during a 2-year period with primary ICD-9 codes of 491, 492, or 496.

MEASUREMENTS

Demographic characteristics, comorbid conditions, hospital utilization for COPD, and vital status.

RESULTS

During the study period, there were 482 index visits with a median follow-up of 1,128 days (3.1 years). Demographic characteristics of the cohort were as follows: mean age 72 years, 56% female, 93% White, and 37% currently married. Mortality increased over time: 5% at 30 days, 9% at 60 days, 11% at 90 days, 16% at 180 days, 23% at 1 year, 32% at 2 years, and 39% at 3 years. At the end of follow-up, 220 (46%) patients had died. On multivariate analysis, independent predictors of mortality were increasing age (hazard ratio [HR] 1.3 per 5-year increase, 95% CI 1.2-1.4), having congestive heart failure (HR 1.6, 95% CI 1.2-2.1), having metastatic solid tumor (HR 3.3, 95% CI 2.0-5.5), and hospital utilization for COPD exacerbation during past year (HR 1.9, 95% CI 1.4-2.6).

CONCLUSION

The mortality rate after an ED visit for COPD exacerbation is quite high. Mortality is related to older age, specific comorbid conditions, and history of prior COPD exacerbations.

Heart failure and chronic obstructive pulmonary disease: diagnostic pitfalls and epidemiology

Heart failure (HF) and chronic obstructive pulmonary disease (COPD) are global epidemics incurring significant morbidity and mortality. The combination presents many diagnostic challenges. Clinical symptoms and signs frequently overlap. Evaluation of cardiac and pulmonary function is often problematic and occasionally misleading. Echocardiography and pulmonary function tests should be performed in every patient. Careful interpretation is required to avoid misdiagnosis and inappropriate treatment. Airflow obstruction, in particular, must be demonstrated when clinically euvolaemic. Very high and very low concentrations of natriuretic peptides have high positive and negative predictive values for diagnosing HF in those with both conditions. Intermediate values are less informative. Both conditions are systemic disorders with overlapping pathophysiological processes. In patients with HF, COPD is consistently an independent predictor of death and hospitalization. However, the impact on ischaemic and arrhythmic events is unknown. Greater collaboration is required between cardiologists and pulmonologists to better identify and manage concurrent HF and COPD. The resulting symptomatic and prognostic benefits outweigh those attainable by treating either condition alone.

Chronic obstructive pulmonary disease in patients admitted with heart failure

OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is an important differential diagnosis in patients with heart failure (HF). The primary aims were to determine the prevalence of COPD and to test the accuracy of self-reported COPD in patients admitted with HF. Secondary aims were to study a possible relationship between right and left ventricular function and pulmonary function.

DESIGN

Prospective substudy.

SETTING

Systematic screening at 11 centres.

SUBJECTS

Consecutive patients (n = 532) admitted with HF requiring medical treatment with diuretics and an episode with symptoms corresponding to New York Heart Association class III-IV within a month prior to admission.

INTERVENTIONS

Forced expiratory volume in 1 s (FEV(1)) and forced vital capacity (FVC) were measured by spirometry and ventricular function by echocardiography. The diagnosis of COPD and HF were made according to established criteria.

RESULTS

The prevalence of COPD was 35%. Only 43% of the patients with COPD had self-reported COPD and one-third of patients with self-reported COPD did not have COPD based on spirometry. The prevalence of COPD in patients with preserved left ventricular ejection fraction (i.e. LVEF >or=45%) was significantly higher than in patients with impaired LVEF (41% vs. 31%, P = 0.03). FEV(1) and FVC were negatively correlated with right ventricular end-diastolic diameter and tricuspid annular plane systolic excursion and FVC positively correlated with systolic gradient across the tricuspid valve.

CONCLUSION

Chronic obstructive pulmonary disease is frequent in patients admitted with HF and self-reported COPD only identifies a minority. The prevalence of COPD was high in both patients with systolic and nonsystolic HF.

Bone marrow-derived progenitor cells contribute to lung remodelling after myocardial infarction

BACKGROUND

Congestive heart failure (CHF) causes structural modifications of the lungs that contribute to the functional limitations of affected subjects. We hypothesized that bone marrow-derived progenitor cells could contribute to lung structural remodelling after myocardial infarction (MI).

METHODS

Wistar rats were irradiated and received a bone marrow transplant (BMT) from green fluorescent protein (GFP) transgenic rats, followed 5 weeks later by coronary artery ligation or sham operation. Five weeks after MI, lung immunofluorescence studies were performed and GFP expression evaluated by Western immunoblotting.

RESULTS

After MI, rats developed lung structural remodelling characterized by myofibroblast (MF) proliferation in the alveolar septa. After BMT, some GFP+ cells were found in the lungs of sham animals. The amount of GFP+ cells in the lungs of MI rats was greatly increased with evidence of differentiation into MFs, as evaluated by co-localization correlation analysis with smooth muscle alpha-actin (P<.01). These cells were particularly abundant in the perivenular regions where they incorporated into the wall of blood vessels. There was a threefold increase in lung GFP protein expression after MI (P=.01).

CONCLUSIONS

After MI, bone marrow-derived progenitor differentiates into lung MFs. This novel pathophysiologic process may contribute to the pulmonary manifestations of CHF and could have significant therapeutic implications.

Pulmonary function changes associated with cardiomegaly in chronic heart failure

BACKGROUND

This study examined the influence of increased cardiac size on maximal lung volumes, forced expiratory airflows, and the diffusing capacity of the lungs in heart failure (HF) patients compared with controls.

METHODS AND RESULTS

Forty-one HF patients of New York Heart Association (NYHA) class: Group A = class I/II (n = 26) and Group B = class III/IV (n = 15) and an equal number matched controls (CTL) were recruited. Participants underwent echocardiography, spirometry, and posteroanterior and lateral chest radiographic evaluation (RAD) for volumetric estimation of the total thoracic cavity (TTC), diaphragm, heart, and lungs. Analysis of variance demonstrated no difference between groups for TTC volume (P = .63). RAD cardiac volumes (% TTC volume) were significantly different among all groups (P < .001). Echocardiograms determined left ventricular mass was elevated in the HF groups compared with the CTL group (P < .001) with no difference between HF groups. Lung volume (% TTC volume) was reduced as a function of disease severity (P < .001). RAD measures of cardiac volume demonstrated the strongest relationship with restrictive lung alterations (t-statistic = -5.627, P < .001 and t-statistic = -4.378, P < .001 for forced vital capacity and forced expiratory volume in 1 second, respectively).

CONCLUSIONS

These results suggest cardiac size may pose significant constraints on the lungs and likely plays a major role in the restrictive breathing patterns often reported in HF patients.

Chronic Respiratory Complications in Pediatric Heart Transplant Recipients

BACKGROUND

The frequency and spectrum of chronic respiratory complications in pediatric heart transplant recipients have not been extensively studied. The aim of this study was to describe the chronic respiratory complications in 126 consecutive pediatric heart transplant recipients.

METHODS

Retrospective review of medical records.

RESULTS

Between 1987 and 2005, 126 (64 males and 62 females) heart transplantations were performed at Freeman Hospital, Newcastle upon Tyne, United Kingdom. The median age at transplantation was 7.4 years (range, 0.1-17) and the median length of follow-up was 6.8 years (range, 0-18.2). Twenty-four patients have died, and 36 have been transferred to adult follow-up, leaving 66 under pediatric follow-up. Chronic respiratory complications have been documented in 33 children (50%). Bronchiectasis has been identified in 10 children, and 12 further children have had recurrent lower respiratory tract infections (without bronchiectasis) requiring long-term antibiotic prophylaxis. Of those with infectious complications, 81% underwent transplantation before 4 years and had deficiency of pneumococcal-specific antibody response. Obstructive sleep apnea has occurred in 5 children, sub-glottic stenosis has occurred in 3, and significant compression of the left main stem bronchus related to a disproportionately large donor heart has occurred in 2. One child had marked mosaic attenuation on chest computed tomography scan indicative of small airways disease.

CONCLUSION

Chronic respiratory complications are common in pediatric heart transplant recipients. The respiratory prognosis for this complex group of patients is usually good, but long-term follow-up by both a respiratory pediatrician and an immunologist is frequently required.

Competition for intrathoracic space reduces lung capacity in patients with chronic heart failure: a radiographic study

BACKGROUND

The purpose of this study was to determine the influence of changes in cardiac size on total lung volume in patients with chronic heart failure compared to control subjects.

METHODS

Forty-four patients and age-, gender-, and height-matched control participants were recruited. All participants underwent posteroanterior and lateral chest radiography for volumetric estimations of the total thoracic cavity (TTC), diaphragm, heart, and lungs. To assess the relationship between chronic heart failure severity and cardiac enlargement, patients with chronic heart failure were classified into groups based on New York Heart Association class, as follows: class I and II, n = 26 (group A); class III and IV, n = 18 (group B).

RESULTS

There was no difference between the groups for TTC volume (TTCV) [p = 0.56]. Cardiac volumes were significantly different between all groups for both the absolute volumes (p < 0.001) were calculated as a percentage of TTCV (p < 0.001), with the largest cardiac volumes in group B (twice the volume of healthy control subjects). When expressed as a percentage of TTCV, there also was a clear reduction in lung volumes as a function of disease severity (p < 0.001).

CONCLUSIONS

The present study demonstrates a close relationship between the severity of heart failure and cardiac size. These changes in cardiac size within a closed thoracic cavity may pose significant constraints on the lungs, resulting in reductions in lung volumes that likely play a major role in the restrictive breathing patterns often reported in patients with chronic heart failure.

Frequent non-cardiac comorbidities in patients with chronic heart failure

Heart failure (HF) in elderly patients is associated with more diffuse symptoms and signs due to the presence of other noncardiac comorbidities. This can cause difficulties in assessing the correct diagnosis and initiating appropriate therapy. The four most frequently occurring noncardiac comorbidities and therapies used to treat them are discussed in the present paper. Hypertension is an important precursor of HF, and is still the most common risk factor for HF in the general population. About 50% of patients with untreated hypertension will develop HF. Pressure overload leads to the development of left ventricular hypertrophy (LVH) and diastolic dysfunction. Diabetes, which occurs in about 20-30% of patients with HF, is an important comorbidity resulting in morphological and metabolic disturbances affecting myocardial blood flow and hormonal regulation leading to a poor outcome and necessitating aggressive conventional treatment. Chronic obstructive pulmonary disease (COPD), occurs in approximately 20-30% of heart failure patients, and may complicate HF treatment, it is therefore important to recognize and treat it effectively. Finally, the early detection of anemia, which occurs in 20-30% of HF patients, is important since it is associated with functional impairment and increased mortality and morbidity. Combined treatment with erythropoietin and intravenous iron has shown beneficial effects on clinical symptoms and morbidity. In conclusion early detection of concomitant diseases in patients with HF is important and should be considered carefully when initiating therapy.

Therapeutic Update: Non-Selective Beta- and Alpha-Adrenergic Blockade in Patients With Coexistent Chronic Obstructive Pulmonary Disease and Chronic Heart Failure

Patients with chronic heart failure (CHF) have a resting restrictive ventilatory defect. Any type of exercise requires patients with CHF to markedly increase their minute ventilation. Patients with chronic obstructive pulmonary disease (COPD) have airflow obstruction that leads to dynamic lung hyperinflation and reduced ventilatory response to exercise. Because exercise is associated with abnormally high minute ventilation in patients with CHF and with a limited minute ventilation increase in patients with COPD, functional capacity is severely impaired in patients with coexistent CHF and COPD. Optimal treatment of both conditions is a prerequisite to maximally improve functional capacity in patients with CHF and COPD. Unfortunately, beta-adrenergic blockade, the current cornerstone of CHF therapy, is frequently omitted in patients with CHF and COPD for fear of inducing bronchoconstriction. Furthermore, when prescribed, beta-adrenergic blockade is often attempted with a moderate dose of metoprolol tartrate, a beta-1-blocker that results in lesser clinical benefits than combined non-selective beta-blockade with carvedilol at the maximally recommended dose. Recent experience indicates that combined non-selective beta- and alpha-blockade with carvedilol is well tolerated in patients with COPD who do not have reversible airway obstruction. Alpha-adrenergic blockade may promote mild bronchodilation that offsets non-selective beta blockade-induced bronchoconstriction in patients with obstructive airway disease.