The association of chronic lung disease with early mortality and respiratory adverse events after aortic valve replacement

Predictors and outcomes of discharge to long-term acute care facilities after cardiac surgery

OBJECTIVE

An increasing number of patients with significant comorbidities present for complex cardiac surgery, with a subgroup requiring discharge to long-term acute care facilities. We aim to examine predictors and mortality after discharge to a long-term acute care facility.

METHODS

From January 1, 2015, to April 30, 2021, all adult cardiac surgeries were queried and patients discharged to long-term acute care facilities were identified. Baseline characteristics, procedures, and in-hospital complications were compared between long-term acute care facility and non-long-term acute care facility discharges. Random forest analysis was conducted to establish predictors of discharge to long-term acute care facilities. Kaplan-Meier survival analysis was used to determine probability of survival over 7 years. Multivariate regression modeling was used to establish predictors of death after long-term acute care facility discharge.

RESULTS

Of 29,884 patients undergoing cardiac surgery, 324 (1.1%) were discharged to a long-term acute care facility. The long-term acute care facility group had higher rates of urgent/emergency operation (54% vs 23%; 10% vs 3%, P < .001) and longer mean cardiopulmonary bypass (167 vs 110 minutes, P < .001). By random forest analysis, emergency/urgent status, longer cardiopulmonary bypass duration, redo surgery, endocarditis, and history of dialysis were the most predictive of discharge to a long-term acute care facility. Although the non-long-term acute care facility group demonstrated greater than 95% survival at 6 months, Kaplan-Meier survival analysis showed 28% 6-month mortality in the long-term acute care facility cohort. Random forest analysis demonstrated that chronic lung disease and postoperative respiratory complications were significant predictors of death at 6 months after discharge to a long-term acute care facility.

CONCLUSIONS

Patients with chronic lung and kidney disease undergoing prolonged procedures are at higher risk to be discharged to long-term acute care facilities after surgery with worse survival. Efforts to minimize postoperative respiratory complications may reduce mortality after discharge to long-term acute care facilities.

Impact of chronic obstructive pulmonary disease on right ventricular function and remodeling after aortic valve replacement

BACKGROUND

Both chronic obstructive pulmonary disease (COPD) and right ventricular (RV) dysfunction are common factors that have been associated with poor prognosis after aortic valve replacement (AVR). Since there is still uncertainty about the impact of COPD on RV function and dilatation in patients undergoing AVR, we sought to explore RV function and remodeling in the presence and absence of COPD as well as their prognostic implications.

METHODS

Patients who received surgical or transcatheter AVR due to severe AS were screened for COPD. Demographic and clinical data were collected at baseline while echocardiographic measurements were performed at baseline and 1 year after AVR. The study end-point was all-cause mortality.

RESULTS

In total 275 patients were included, with 90 (33%) patients having COPD. At 1-year follow-up, mild worsening of tricuspid annular planar systolic excursion and RV dilatation were observed in patients without COPD, while there were significant improvements in RV longitudinal strain, RV wall thickness but dilatation of RV outflow tract distal dimension in the COPD group compared to the baseline. On multivariable analysis, the presence of COPD provided significant incremental prognostic value over RV dysfunction and remodeling.

CONCLUSIONS

At 1-year after AVR, RV function and dimensions mildly deteriorated in non-COPD group whereas COPD group received significant benefit of AVR in terms of RV function and hypertrophy. COPD was independently associated with >2-fold all-cause mortality and had incremental prognostic value over RV dysfunction and remodeling.

Association Between Chronic Obstructive Pulmonary Disease and All-Cause Mortality After Aortic Valve Replacement for Aortic Stenosis

Chronic obstructive pulmonary disease (COPD) and aortic stenosis (AS) are the most common diseases in which age plays a major role in the increase of their prevalence and when they co-exist, the outcomes prognosis worsens significantly. The aim of the present study was to evaluate the association between pulmonary functional parameters and all-cause mortality after aortic valve replacement (transcatheter or surgical). A total of 400 patients with severe AS and preoperative pulmonary functional test were retrospectively analyzed. Echocardiography and pulmonary functional parameters before aortic valve replacement were collected. COPD severity was defined according to criteria from the Society of Thoracic Surgeons. COPD was present in 128 patients (32%) with severe AS. Patients without COPD had smaller left ventricular (LV) mass and LV end-systolic volume and better LV function than the group with COPD. During a median follow-up of 32 months, 92 patients (23%) died. The survival rates were significantly lower in patients with moderate and severe COPD (log-rank p = 0.003). In the multivariable Cox regression analysis, any grade of COPD was associated with an approximately 2-fold increased risk of all-cause mortality (hazard ratio 1.933; 95% confidence interval 1.166 to 3.204; p = 0.011 for mild COPD and hazard ratio 2.028; 95% confidence interval 1.154 to 3.564; p = 0.014 for moderate or severe COPD). In addition to other clinical factors, any grade of COPD was associated with 2-fold increased risk of all-cause mortality.

Influence of reduced diffusing capacity and FEV1 on outcome after cardiac surgery

BACKGROUND

Impaired lung function is a well-known risk factor in cardiac surgery patients and reduced forced expiratory volume in 1 second (FEV₁ ) is associated with increased mortality. However, there is limited knowledge regarding the influence of impaired diffusing capacity of the lungs for carbon monoxide (DLCO) in unselected cardiac surgery patients. The aim of this study was to investigate the association of impaired DLCO and/or reduced FEV₁ on post-operative mortality and morbidity in cardiac surgery patients.

METHODS

In a prospective cohort study, 390 patients scheduled for elective cardiac surgery underwent preoperative lung function test including spirometry and DLCO measurements. We defined reduced FEV₁ as FEV₁ below lower limit of normal (LLN) and impaired DLCO as DLCO <60% of predicted.

RESULTS

Mortality within 1 year (90-570 days) was significantly higher in patients with impaired DLCO (12% vs 3%, P = .010) and with reduced FEV₁ (9% vs 3%, P = .028). Mortality was higher in patients with impaired DLCO both in the presence and absence of FEV₁  < LLN. In multivariate analysis, only impaired DLCO [OR: 3.3, 95% confidence interval (CI) 1.4-7.5; P = .005] and age (OR: 1.1 per year, 95% CI 1.0-1.2; P = .001) were independent predictors of the combined outcome of mortality and prolonged intensive care unit (ICU) stay. Impaired DLCO was also associated with post-operative respiratory complications.

CONCLUSION

In patients undergoing elective cardiac surgery, preoperative impaired FEV₁ and DLCO were associated with increased mortality and morbidity. In multivariate analysis, only DLCO and age were independent predictors of a combined outcome of mortality and prolonged ICU stay.

Infective Endocarditis After Transcatheter Versus Surgical Aortic Valve Replacement: A Meta-Analysis

We determined the incidence, clinical characteristics, and risk factors of post-transcatheter aortic valve replacement (TAVR)-associated infective endocarditis (IE). We compared the incidence of IE after TAVR versus after surgical aortic valve replacement (SAVR). The incidence rate of IE 1-year post-TAVR was 0.9% (95% confidence interval [CI]: 0.8-1.0). Transcatheter aortic valve replacement was associated with significantly reduced IE incidence (incidence rate ratio: 0.69, 95% CI: 0.52-0.92, P = .011) compared with SAVR. In patients with TAVR IE, the pooled in-hospital mortality was 37.8% (95% CI: 32.4-43.3, I ² = 54.9%). Pooled adjusted hazard ratio (HR) revealed that peri-procedural peripheral artery disease (HR: 4.02, 95% CI: 2.28-7.10, P < .0001), moderate or severe residual aortic regurgitation (HR: 2.34, 95% CI: 1.53-3.59, P < .0001), orotracheal intubation (HR: 2.13, 95% CI: 1.19-3.82, P = .011), and male gender (HR: 1.70, 95% CI: 1.47-1.97, P < .0001) were risk factors for post-TAVR IE. Post-TAVR IE is a life-threatening complication often resulting in in-hospital mortality. The current evidence-based meta-analysis to identify risk factors may lead to the development of effective preventive and therapeutic strategies for post-TAVR IE to ultimately improve patient outcomes.

Fibrotic Lung Disease at CT Predicts Adverse Outcomes in Patients Undergoing Transcatheter Aortic Valve Replacement

Purpose

To evaluate the relationship between CT findings of diffuse lung disease and post-transcatheter aortic valve replacement (TAVR) outcomes.

Materials and Methods

Retrospective review of pre-TAVR CT scans obtained during 2012-2017 was conducted. Emphysema, reticulation, and honeycombing were separately scored using a five-point scale and applied to 10 images per examination. The fibrosis score was the sum of reticulation and honeycombing scores. Lung diseases were also assessed as dichotomous variables (zero vs nonzero scores). The two outcomes evaluated were death and the composite of death and readmission.

Results

The study included 373 patients with median age of 84 years (age range, 51-98 years; interquartile range, 79-88 years) and median follow-up of 333 days. Fibrosis and emphysema were present in 66 (17.7%) and 95 (25.5%) patients, respectively. Fibrosis as a dichotomous variable was independently associated with the composite of death and readmission (hazard ratio [HR], 1.54; P = .030). In those without known chronic lung disease (CLD) (HR, 3.09; P = .024) and those without airway obstruction, defined by a ratio of forced expiratory volume in 1 second to the forced vital capacity greater than or equal to 70% (HR, 1.67, P = .039), CT evidence of fibrosis was a powerful predictor of adverse events. Neither emphysema score nor emphysema as a dichotomous variable was an independent predictor of outcome.

Conclusion

The presence of fibrosis on baseline CT scans was an independent predictor of adverse events after TAVR. In particular, fibrosis had improved predictive value in both patients without known CLD and patients without airway obstruction.Supplemental material is available for this article.© RSNA, 2020.

Transcatheter vs surgical aortic valve replacement in patients with interstitial lung disease

BACKGROUND

Patients with underlying interstitial lung disease (ILD) who undergo cardiac surgery are at high risk of postoperative pulmonary complications. It remains unclear if transcatheter aortic valve replacement (TAVR) offers any benefit over surgical aortic valve replacement (SAVR) in ILD patients with severe aortic stenosis.

METHODS

All adult patients with a diagnosis of ILD who underwent either a TAVR or isolated SAVR between January 2002 and December 2017 were retrospectively reviewed. Operative mortality, 30-day readmissions, and adjusted 1-year survival were compared between the two cohorts.

RESULTS

The overall cohort included 52 TAVR and 74 SAVR patients. While TAVR patients were significantly older (77.2 vs 72.9 years) with higher Society of Thoracic Surgeons predicted risk of mortality (STS-PROM) scores compared with SAVR patients (6.29 vs 4.49; all P < .02), operative mortality was similar (5.8% vs 4.1%; P =  .45). Rates of postoperative stroke, permanent pacemaker implantation, reintubation, and 30-day readmissions did not differ between the two groups (all P > .46). However, TAVR was associated with significantly shorter hospital and intensive care unit (ICU) length of stay, shorter ventilation times, and less requirement for ICU admission (all P < .05). Thirty-day readmissions and adjusted 1-year survival were also similar between the two groups (hazard ratio for TAVR vs SAVR = 1.34; 95% CI: 0.7-2.6).

CONCLUSIONS

Among ILD patients with symptomatic aortic stenosis, TAVR was associated with comparable operative and risk-adjusted 1-year survival to SAVR. TAVR patients also had shorter ventilator times, ICU and hospital stay despite being at higher risk. Together, our findings suggest that TAVR may be a better option in this unique cohort.

Significance of Interstitial Lung Disease on Outcomes Following Cardiac Surgery

Interstitial lung disease (ILD) is a known risk factor for noncardiac surgery due to acute pulmonary exacerbations but its impact after cardiac surgery is not known. We examined perioperative outcomes and risk factors for long-term survival in ILD patients who underwent cardiac surgery. From January 2002 to June 2017, 294 cardiac surgery patients with a previous ILD diagnosis, including 75 patients with idiopathic pulmonary fibrosis (IPF), were identified. A comparison cohort of 1,481 non-ILD patients was selected based on a priori variables. Long-term survival was evaluated using Cox proportional hazard modeling. Median follow-up was 6.4 years. ILD patients had higher postoperative mortality, reintubation rates, longer intensive care unit stay, and higher 30-day readmission rates (all p <0.05). Kaplan-Meier estimates of survival at 1, 5, and 10 years were 89%, 62%, and 37% for the non-IPF ILD cohort, 89%, 50%, and 13% for the IPF cohort, and 95%, 82%, and 67% for the comparison cohort, respectively (overall p <0.001). These significant differences in survival persisted in our risk-adjusted survival analysis. Adjusted survival analysis identified IPF (hazard ratio 3.04) and ILD (non-IPF; hazard ratio 1.78) as significant contributors to all-cause mortality. However, there were no changes in pulmonary function tests after 48 months postprocedure. In conclusion, ILD patients who underwent cardiac surgery have increased operative mortality, reintubation rates, longer intensive care unit, and higher 30-day readmissions compared with non-ILD patients. Moreover, severity of ILD, especially in IPF, appears to be associated with shorter long-term survival. In these patients, pulmonary risk stratification and multidisciplinary team approach are crucial.

Respiratory virus of severe pneumonia in South Korea: Prevalence and clinical implications

Background

Severe viral pneumonia is associated with a high mortality rate. However, due to the vulnerability of critically ill patients, invasive diagnostic methods should be performed with caution in the intensive care unit (ICU). It would be helpful if the prevalence, risk factors, and clinical impact of virus detection are elucidated.

Methods

We evaluated patients with severe pneumonia between January 1^st 2008 and December 31^st 2015. Reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed for 8 respiratory viruses when viral pathogen could not be excluded as the origin of severe pneumonia. The baseline characteristics, laboratory results, microbiological findings, and clinical outcomes of the patients were analyzed.

Results

Of the 2,347 patients admitted to the medical ICU, 515 underwent RT-PCR for respiratory viruses, 69 of whom had positive results. The detection rate was higher during the winter, with a community onset, in patients with history of recent chemotherapy, and low platelet count. Additional bronchoscopic sampling along with upper respiratory specimen increased the yield of viral detection. Respiratory syncytial virus was the most common pathogen detected, while influenza A was the most common virus with bacterial coinfection. Respiratory virus detection led to changes in clinical management in one-third of the patients.

Conclusions

The detection of viral pathogens in patients with severe pneumonia is not rare, and can be more common in certain group of patients. Invasive sampling for RT-PCR can be helpful, and such detection can lead to positive changes in clinical management.

Transcatheter Aortic Valve Implantation Versus Surgical Aortic Valve Replacement in Lower-Surgical-Risk Patients With Chronic Obstructive Pulmonary Disease

Respiratory complications are a major factor contributing to postoperative morbidity and mortality, especially in patients with chronic obstructive pulmonary disease (COPD). Our objective was to compare the rate of respiratory complications in patients with COPD with severe aortic stenosis who underwent transcatheter aortic valve implantation (TAVI) versus surgical aortic valve replacement (SAVR). Low-to-intermediate surgical-risk patients with moderate or severe COPD who underwent TAVI or SAVR at 2 tertiary centers were included in this study. COPD was defined by the Global Initiative for Chronic Lung Disease classification. The primary end point was the 30-day composite of respiratory mortality, prolonged ventilation (>24 hours), the need for reintubation for respiratory causes, tracheostomy, acute respiratory distress syndrome, pneumonia, or pneumothorax. The inverse probability of treatment weighting was determined to reduce baseline imbalance between the 2 groups. A total of 321 patients (mean age 72.4 ± 9.3 years old, 74.5% male, mean Society of Thoracic Surgeons predicted risk of mortality 3.8 ± 1.9%, mean forced expiratory volume 1: 59 ± 13%) were included in the analysis. TAVI was performed in 122 patients, whereas 199 underwent SAVR. There were no differences between the 2 groups regarding the composite respiratory primary end point (SAVR 10.6%, TAVR 7.4%, adjusted odds ratio 0.57, 95% confidence interval 0.20 to 1.65, p = 0.30). Transfemoral TAVI without general anesthesia (28 patients) was associated with the lowest rate of respiratory complications (3.6%). Among patients with moderate or severe COPD at low-to-intermediate surgical risk, TAVI patients had a similar rate of 30-day major pulmonary complications compared with SAVR patients despite a higher baseline risk profile. Future studies should further investigate whether TAVI is associated with reduced respiratory complications, comparing transfemoral TAVI recipients treated with local anesthesia with their SAVR counterparts.

Minimally Invasive Aortic Valve Replacement via Right Anterior Minithoracotomy and Central Aortic Cannulation

Objective

This study reports the evolution of a minimally invasive aortic valve replacement (mini-AVR) technique that uses a right anterior minithoracotomy approach with central cannulation, for a 13-year period. This technique has become our standard approach for isolated primary AVR in nearly all patients.

Methods

This observational study evaluated perioperative clinical outcomes of patients 18 years or older who underwent mini-AVR from November 2003 to June 2015.

Results

The mini-AVR technique was used in 202 patients during two periods of 2003 to 2009 (n = 65, “early”) and 2010 to 2015 (n = 137, “late”). The mean ± SD age was 72.5 ± 12.9 years and 60% were male. Demographic parameters were statistically similar between the study periods, except for increased body weight in the later period (75.3 ± 14.7 vs 80.9 ± 20.8 kg, P = 0.03). The mean cardiopulmonary bypass and aortic cross-clamp times were significantly different by each year and Bonferroni adjustment, with significant decreases in cardiopulmonary bypass and aortic cross-clamp times beginning 2006. Compared with the early study period, late study period patients were more often extubated intraoperatively (52% vs 12%, P < 0.001), had less frequent prolonged ventilator use postoperatively (6% vs 16%, P = 0.018), required fewer blood transfusions (mean, 2.0 ± 2.3 U vs 3.6 ± 3.0 U; P = 0.011), and had shorter postoperative stay (6.3 ± 4.5 days vs 8.0 ± 5.9 days, P = 0.026). Numerically, fewer postoperative strokes (1% vs 6%, P = 0.09) and fewer reoperations for bleeding (3% vs 6%, P = 0.3) occurred in the late period. In-hospital mortality did not differ (1/65 early vs 3/137 late).

Conclusions

Overall mini-AVR intraoperative and postoperative clinical outcomes improved for this 13-year experience.

Preoperative pulmonary function tests predict mortality after surgical or transcatheter aortic valve replacement

OBJECTIVES

To determine the role of preoperative pulmonary function tests (PFTs) in patients with aortic stenosis (AS) evaluated for aortic valve replacement (AVR), and to evaluate the association between lung disease and mortality in specific subgroups.

METHODS

Between 2008 and 2013, 535 patients with preoperative PFTs underwent AVR (transcatheter AVR [TAVR], n = 246; surgical AVR [SAVR], n = 289). The severity of lung disease determined by the Society of Thoracic Surgeons (STS) definition was evaluated in those with and without a clinical suspicion for lung disease (smoking, inhaled steroids/bronchodilators, or home oxygen). The association between lung disease and 1-year mortality was evaluated.

RESULTS

Of the 186 patients (35%) without suspected lung disease, 39 (21%) had moderate/severe lung disease by PFT analysis. Among all patients, 1-year mortality was 12% in those with no lung disease, 17% in those with no mild lung disease, 22% in those with moderate lung disease, and 31% in those with severe lung disease (P < .001, log-rank test). After adjustment, moderate/severe lung disease was associated with increased 1-year mortality (adjusted hazard ratio, 2.07; 95% confidence interval, 1.30-3.29; P = .002); this association was not altered by smoking history, suspicion of lung disease, New York Heart Association class, or AVR type (interaction P value nonsignificant for all).

CONCLUSIONS

In patients with AS evaluated for AVR, the STS risk score is significantly influenced by the severity of lung disease, which is determined predominantly by PFT results. Even when lung disease is not suspected, PFTs are abnormal in many patients undergoing AVR. Moderate/severe lung disease, diagnosed predominantly by PFTs, is an independent predictor of mortality after SAVR or TAVR. Collectively, these findings suggest that PFTs should be a routine part of the risk stratification of patients considered for AVR.