Pulmonary Limitations in Heart Failure

Association of COPD with adverse outcomes in heart failure patients with preserved ejection fraction

We performed a systematic review and meta-analysis to detect the impact of chronic obstructive pulmonary disease (COPD) on the prognosis of heart failure patients with preserved ejection fraction (HFpEF). We systematically screened eligible literature from three electronic databases, PubMed, EMBASE and Cochrane Library, up to April 2023. Two researchers participated in data collection independently. Risk ratios (RRs) from included studies with 95% confidence intervals (CIs) were pooled in the Review Manager version 5.40 software using a random-effects model for analysis. A total of 11 studies (3 post hoc analyses of RCTs and 8 observational studies) with 18 602 participants were included in this meta-analysis. After pooling all the data from eligible studies, our results indicated that COPD was associated with an increased risk of hospitalization (RR = 1.66, 95% CI, 1.47-1.87, P < 0.00001), mortality (RR = 1.62, 95% CI, 1.34-1.95, P < 0.00001), and the composition of hospitalization or mortality (RR = 1.84, 95% CI, 1.35-2.51, P < 0.001) in patients with HFpEF. In a subgroup analysis, the risks of cardiovascular-related mortality (RR = 1.59, 95% CI, 1.30-1.93, P < 0.00001) and post-discharge mortality risk (RR = 2.57, 1.34-4.93, P < 0.01) were increased in HFpEF patients comorbid with COPD, and these associations were also detected in HF-caused hospitalization (RR = 1.64, 95% CI, 1.44-1.87, P < 0.00001). Evidence from existing studies supported that COPD was an independent prognostic risk factor for patients with HFpEF. Developing rapid clinical diagnostic indicators and early use of novel drugs such as SGLT-2 and ARNI may improve the prognosis of this population, deserving further study.

Prevalence of respiratory failure and use of mechanical ventilation in heart failure patients undergoing left atrial appendage occlusion device implantation

BACKGROUND

We sought to evaluate respiratory complications in heart failure patients undergoing left atrial appendage occlusion (LAAO) for stroke prevention in atrial fibrillation.

METHODS

Adult admissions (>18 years) undergoing LAAO during 2016-2020 were identified from the National Inpatient Sample. Heart failure (HF) was stratified into systolic (SHF) and diastolic heart failure (DHF) and were compared to those without HF. Outcomes of interested included acute respiratory failure, use of non-invasive and invasive mechanical ventilation, and in-hospital mortality.

RESULTS

Of 74,440 admissions for atrial fibrillation undergoing LAAO, SHF and DHF were noted in 8335 (11.2%) and 10,925 (14.7%), respectively. The SHF cohort was predominantly male (78%) whereas DHF cohort were female (53%). Compared to those without HF, presence of SHF (2.3% vs. 0.6%; adjusted odds ratio [OR] 1.61 [95% confidence interval {CI} 1.10-2.36]; p = 0.01) and DHF (2.8% vs. 0.6%; adjusted OR 2.20 [95% CI 1.58-3.06]; p < 0.001) were associated with higher rates of acute respiratory failure. SHF (1.7% vs. 0.6%; adjusted OR 1.70 [95% CI 1.07-2.71]; p = 0.02) group but not DHF (1.2% vs. 0.6%; adjusted OR 1.21 [95% CI 0.78-1.89]; p = 0.39) was associated with higher rates of non-invasive ventilation, whereas the DHF group (0.9% vs. 0.2%; adjusted OR 1.91 [95% CI 1.08-3.34]; p = 0.02) but not SHF (0.8% vs. 0.2%; adjusted OR 1.54 [95% CI 0.83-2.84]; p = 0.17) was associated with higher rates of invasive mechanical ventilation use. In-hospital mortality was comparable between cohorts.

CONCLUSION

Compared to those without HF, atrial fibrillation admissions with HF undergoing LAAO had higher rates of acute respiratory failure and mechanical ventilation rates without differences in in-hospital mortality.

Cardiopulmonary interactions in left heart failure

The primary impact of ventilation and ventilatory efforts on left ventricular (LV) function in left ventricular dysfunction relate to how changes in intrathoracic pressure (ITP) alter the pressure gradients for venous return into the chest and LV ejection out of the chest. Spontaneous inspiratory efforts by decreasing ITP increase both of these pressure gradients increasing venous blood flow and impeding LV ejection resulting in increased intrathoracic blood volume. In severe heart failure states when lung compliance is reduced, or airway resistance is increased these negative swings in ITP can be exacerbated leading to LV failure and acute cardiogenic pulmonary edema. By merely reversing these negative swings in ITP by the use of non-invasive continuous positive airway pressure (CPAP), these profoundly detrimental forces can be immediately reversed, and cardiovascular stability can be restored in moments. This forms the clinical rationale for the immediate use of CPAP for the treatment of acute cardiogenic pulmonary edema. Increasing ITP during positive pressure ventilation decreases the pressure gradients for venous return and LV ejection decreasing intrathoracic blood volume. In a hypovolemic patient even with LV dysfunction this can result in hypotension due to inadequate LV preload. Minor increases in ITP as occur using pressure-limited positive-pressure ventilation primarily reverse the increased LV afterload of negative swings in ITP and if fluid overload was already present, minimally alter cardiac output. The effect of changes in lung volume on LV function are related primarily to its effects on right ventricular (RV) function through changes in pulmonary vascular resistance and overdistention (hyperinflation). In acute lung injury with alveolar collapse, positive pressure ventilation may reduce pulmonary vascular resistance if alveolar recruitment predominates. Hyperinflation, however, impedes diastolic filling while simultaneously increasing pulmonary vascular resistance. Thus, increasing lung volume can reduce RV afterload by reversing hypoxic pulmonary vasoconstriction or increase afterload by overdistention. Hyperinflation can also impede RV filling. All of these processes can be readily identified at the bedside using echocardiography.

Alveolar Dead Space Is Augmented During Exercise in Patients With Heart Failure With Preserved Ejection Fraction

BACKGROUND

Patients with heart failure with preserved ejection fraction (HFpEF) exhibit many cardiopulmonary abnormalities that could result in V˙/Q˙ mismatch, manifesting as an increase in alveolar dead space (VDalveolar) during exercise. Therefore, we tested the hypothesis that VDalveolar would increase during exercise to a greater extent in patients with HFpEF compared with control participants.

RESEARCH QUESTION

Do patients with HFpEF develop VDalveolar during exercise?

STUDY DESIGN AND METHODS

Twenty-three patients with HFpEF and 12 control participants were studied. Gas exchange (ventilation [V˙E], oxygen uptake [V˙o2], and CO2 elimination [V˙co2]) and arterial blood gases were analyzed at rest, twenty watts (20W), and peak exercise. Ventilatory efficiency (evaluated as the V˙E/V˙co2 slope) also was measured from rest to 20W in patients with HFpEF. The physiologic dead space (VDphysiologic) to tidal volume (VT) ratio (VD/VT) was calculated using the Enghoff modification of the Bohr equation. VDalveolar was calculated as: (VD / VT × VT) - anatomic dead space. Data were analyzed between groups (patients with HFpEF vs control participants) across conditions (rest, 20W, and peak exercise) using a two-way repeated measures analysis of variance and relationships were analyzed using Pearson correlation coefficient.

RESULTS

VDalveolar increased from rest (0.12 ± 0.07 L/breath) to 20W (0.22 ± 0.08 L/breath) in patients with HFpEF (P < .01), whereas VDalveolar did not change from rest (0.01 ± 0.06 L/breath) to 20W (0.06 ± 0.13 L/breath) in control participants (P = .19). Thereafter, VDalveolar increased from 20W to peak exercise in patients with HFpEF (0.37 ± 0.16 L/breath; P < .01 vs 20W) and control participants (0.19 ± 0.17 L/breath; P = .03 vs 20W). VDalveolar was greater in patients with HFpEF compared with control participants at rest, 20W, and peak exercise (main effect for group, P < .01). Moreover, the increase in VDalveolar correlated with the V˙E/V˙co2 slope (r = 0.69; P < .01), which was correlated with peak V˙o2peak (r = 0.46; P < .01) in patients with HFpEF.

INTERPRETATION

These data suggest that the increase in V˙/Q˙ mismatch may be explained by increases in VDalveolar and that increases in VDalveolar worsens ventilatory efficiency, which seems to be a key contributor to exercise intolerance in patients with HFpEF.

Comprehensive and Safe Decongestion in Acutely Decompensated Heart Failure

PURPOSE OF THE REVIEW

Progressive intravascular, interstitial, and alveolar fluid overload underlies the transition from compensated to acutely decompensated heart failure and loop diuretics are the mainstay of treatment. Adverse effects and resistance to loop diuretics received much attention while the contribution of a depressed cardiac output to diuretic resistance was downplayed.

RECENT FINDINGS

Analysis of experience with positive inotropic agents, especially dobutamine, indicates that enhancement of cardiac output is not consistently associated with increased renal blood flow. However, urinary output and renal sodium excretion increase likely due to dobutamine-mediated decrease in renal and systemic reduced activation of sympathetic nervous- and renin-angiotensin-aldosterone system. Mechanical circulatory support with left ventricular assist devices ascertained the contribution of low cardiac output to diuretic resistance and the pathogenesis and progression of kidney disease in acutely decompensated heart failure. Diuretic resistance commonly occurs in acutely decompensated heart failure. However, failure to resolve fluid overload despite high doses of loop diuretics should alert to the presence of a low cardiac output state.

Restrictions of VC and DLCO in relation to asbestos-related computed tomographic findings quantified by ICOERD-based parameters

BACKGROUND

Even almost 30 years after the ban on the use of asbestos in Germany, the effects of asbestos are still highly relevant in everyday clinical practice in occupational medicine. The aim of this study was to further investigate the significance of essential parameters of both pulmonary function diagnostics and imaging techniques (low-dose HR-TCT) for the prevention and early detection of asbestos-related morphological and functional lung changes.

METHODS

Data from spirometry, body plethysmography and diffusion capacity, as well as CT images of the thorax, were retrospectively studied from 72 patients examined between 2017 and 2019 at the Institute for Occupational and Maritime Medicine (ZfAM), Hamburg, Germany. The subjects were divided into four subgroups according to the presence of comorbidities (concomitant cardiac diseases, obstructive ventilatory disorder, pulmonary function pattern consistent with emphysema, and no other pulmonary or cardiac diseases). These subgroups were analysed in addition to the overall collective. The CT images were evaluated according to the International Classification of Occupational and Environmental Respiratory Diseases (ICOERD) with radiological expertise. In addition, some asbestos-related parameters were newly quantified, and corresponding scores were defined based on ICOERD. Statistical analysis included the use of correlations and fourfold tables with calculation of Spearman's rho (ρ), Cohen's κ, and accuracy.

RESULTS

Vital capacity (VC) is slightly reduced in the total collective compared to the normal population (mean 92% of predicted value), while diffusion capacity for CO (DLCO) shows predominantly pathological values, mean 70% of the respective predicted value. The CO transfer coefficient (DLCO/VA), which refers to alveolar volume (VA), also shows slightly decreased values (mean 87% pred.). Seventy-nine percent of patients (n = 57) had signs of pulmonary fibrosis on CT scans, and pleural plaques appeared in 58 of 72 patients (81%). Of the newly quantified additional parameters, particularly frequently described findings are subpleural curvilinear lines (SC, n = 39) and parenchymal bands (PB, n = 29). VC correlates well with the expression of pleural plaques (ρ = - 0.273, P < 0.05), and DLCO measures show a better correlation with fibrosis score (ρ = - 0.315, P < 0.01). A third, newly developed score, which includes the extent of pleural plaques and additional subpleural parameters instead of fibrosis parameters, shows significant correlations for both VC and DLCO (ρ = - 0.283, - 0.274, resp.; both P < 0.05).

DISCUSSION

The importance of spirometry (VC) and diffusion capacity measurement (DLCO) as essential diagnostic procedures for the early detection of asbestos-related changes ‒ also including patients with relevant concomitant cardiac or pulmonary diseases ‒ was confirmed. Significant and better correlations between lung function changes (VC and DLCO) and abnormal CT findings are seen when parenchymal bands (PB), subpleural curvilinear lines (SC), and rounded atelectasis (RA) are quantitatively included into the evaluation, in addition to assessing the extent of pleural plaques alone. Therefore, when assessing CT images according to ICOERD, these parameters should also be quantified.

Early Detection of Worsening Heart Failure in Patients at Home Using a New Telemonitoring System of Respiratory Stability

BACKGROUND

Early detection of worsening heart failure (HF) with a telemonitoring system crucially depends on monitoring parameters. The present study aimed to examine whether a serial follow up of all-night respiratory stability time (RST) built into a telemonitoring system could faithfully reflect ongoing deterioration in HF patients at home and detect early signs of worsening HF in a multicenter, prospective study.Methods and Results:Seventeen subjects with New York Heart Association class II or III were followed up for a mean of 9 months using a newly developed telemonitoring system equipped with non-attached sensor technologies and automatic RST analysis. Signals from the home sensor were transferred to a cloud server, where all-night RSTs were calculated every morning and traced by the monitoring center. During the follow up, 9 episodes of admission due to worsening HF and 1 episode of sudden death were preceded by progressive declines of RST. The receiver operating characteristic curve demonstrated that the progressive or sustained reduction of RST below 20 s during 28 days before hospital admission achieved the highest sensitivity of 90.0% and specificity of 81.7% to subsequent hospitalization, with an area under the curve of 0.85.

CONCLUSIONS

RST could serve as a sensitive and specific indicator of worsening HF and allow the detection of an early sign of clinical deterioration in the telemedical management of HF.

Relação da Função Pulmonar e da Força Inspiratória com Capacidade Aeróbica e com Prognóstico na Insuficiência Cardíaca

Fundamento

A espirometria é subutilizada na insuficiência cardíaca (IC) e não está claro o grau de associação de cada defeito com a capacidade de exercício e com o prognóstico desses pacientes.

Objetivo

Determinar a relação da %CVF prevista (ppCVF) e do VEF₁/CVF contínuos com: 1) pressão inspiratória máxima (PImáx), fração de ejeção do ventrículo esquerdo (FEVE) e desempenho ao exercício; e 2) prognóstico, para o desfecho composto de morte cardiovascular, transplante cardíaco ou implante de dispositivo de assistência ventricular.

Métodos

Coorte de 111 participantes com IC (estágios AHA C/D) sem pneumopatia; foram submetidos a espirometria, manovacuometria e teste cardiopulmonar máximo. As magnitudes de associação foram verificadas por regressões lineares e de Cox (HR; IC 95%), ajustadas para idade/sexo, e p <0,05 foi considerado significativo.

Resultados

Com idade média 57±12 anos, 60% eram homens, 64% em NYHAIII. A cada aumento de 10% no VEF₁/CVF [β 7% (IC 95%: 3-10)] e no ppCVF [4% (2-6)], foi associado à reserva ventilatória (VRes); no entanto, apenas o ppCVF associado à PImáx [3,8cmH₂O (0,3-7,3)], à fração de ejeção do ventrículo esquerdo (FEVE) [2,1% (0,5-3,8)] e ao VO₂ pico [0,5mL/kg/min (0,1-1,0)], considerando idade/sexo. Em 2,2 anos (média), ocorreram 22 eventos; tanto FEV1/FVC (HR 1,44; IC 95%: 0,97-2,13) quanto ppCVF (HR 1,13; 0,89-1,43) não foram associados ao desfecho. Apenas no subgrupo FEVE ≤50% (n=87, 20 eventos), VEF₁/CVF (HR 1,50; 1,01-2,23), mas não ppCVF, foi associado a risco.

Conclusão

Na IC crônica, ppCVF reduzido associou-se a menor PImáx, FEVE, VRes e VO₂ pico, mas não distinguiu pior prognóstico em 2,2 anos de acompanhamento. Entretanto, VEF₁/CVF associou-se apenas com VRes, e, em participantes com FEVE ≤50%, o VEF₁/CVF reduzido mostrou pior prognóstico proporcional. Portanto, VEF₁/CVF e ppFVC contribuem para melhor fenotipagem de pacientes com IC.

Exercise Dynamic of Patients with Chronic Heart Failure and Reduced Ejection Fraction

PURPOSE OF REVIEW

Exercise causes various dynamic changes in all body parts either in healthy subject or in heart failure (HF) patients. The present review of current knowledge about HF patients with reduced ejection fraction focuses on dynamic changes along a "metabo-hemodynamic" perspective.

RECENT FINDINGS

Studies on the dynamic changes occurring during exercise span many years. Thanks to the availability of advanced methods, it is nowadays possible to properly characterize respiratory, hemodynamic, and muscular function adjustments and their mismatch with the pulmonary and systemic circulations. Exercise is a dynamic event that involves several body functions. In HF patients, it is important to know at what level the limitation takes place in order to better manage these patients and to optimize therapeutic strategies.