Esophageal motor disease and reflux patterns in patients with advanced pulmonary disease undergoing lung transplant evaluation

Pulmonary and esophageal function in lung transplantation: Fundamental principles and clinical application

The lungs and esophagus have a close anatomical and physiological relationship. Over the years, reflux-induced pulmonary injury has gained wider recognition, but the full effects of pulmonary disease on esophageal function are still unknown. Intrathoracic pressure dynamics potentially affect esophageal function, especially in patients with end-stage lung disease, both obstructive and restrictive. Lung transplantation is the only viable option for patients with end-stage pulmonary disease and has provided us with a unique opportunity to study these effects as transplantation restores the intrathoracic environment. Esophageal and foregut functional testing before and after transplantation provide insights into the pathophysiology of the foregut-pulmonary axis, such as how underlying pulmonary disease and intrathoracic pressure changes affect esophageal physiology. This review summarizes the available literature and shares the research experience of a lung transplant center, covering topics such as pre- and posttransplant foregut function, esophageal motility in lung transplant recipients, immune-mediated mechanisms of graft rejection associated with gastroesophageal reflux, and the role of antireflux surgery in this population.

Acute transcutaneous electrical stimulation (TES) augments esophageal contractility in patients with weak peristalsis

BACKGROUND

Lung transplantation (LTx) remains controversial in patients with absent peristalsis (AP) given the increased risk for gastroesophageal reflux (GER), and chronic lung allograft dysfunction. Furthermore, specific treatments to facilitate LTx in those with AP have not been widely described. Transcutaneous Electrical Stimulation (TES) has been reported to improve foregut contractility in LTx patients and therefore we hypothesize that TES may augment the esophageal motility of patients with ineffective esophageal motility (IEM).

METHODS

We included 49 patients, 14 with IEM, 5 with AP, and 30 with normal motility. All subjects underwent standard high-resolution manometry and intraluminal impedance (HRIM) with additional swallows as TES was delivered.

RESULTS

TES induced a universal impedance change observable in real-time by a characteristic spike activity. TES significantly augmented the contractile vigor of the esophagus measured by the distal contractile integral (DCI) in patients with IEM [median DCI (IQR) 0 (238) mmHg-cm-s off TES vs. 333 (858) mmHg-cm-s on TES; p = .01] and normal peristalsis [median DCI (IQR) 1545 (1840) mmHg-cm-s off TES vs. 2109 (2082) mmHg-cm-s on TES; p = .01]. Interestingly, TES induced measurable contractile activity (DCI > 100 mmHg-cm-s) in three out of five patients with AP [median DCI (IQR) 0 (0) mmHg-cm-s off TES vs. 0 (182) mmHg-cm-s on TES; p < .001].

CONCLUSION

TES acutely augmented contractile vigor in patients with normal and weak/ AP. The use of TES may positively impact LTx candidacy, and outcomes for patients with IEM/AP. Nevertheless, further studies are needed to determine the long-term effects of TES in this patient population.

Ineffective esophageal motility is associated with acute rejection after lung transplantation independent of gastroesophageal reflux

BACKGROUND

Gastroesophageal reflux is associated with poorer outcomes after lung transplant, likely through recurrent aspiration and allograft injury. Although prior studies have demonstrated a relationship between impedance-pH results and transplant outcomes, the role of esophageal manometry in the assessment of lung transplant patients remains debated, and the impact of esophageal dysmotility on transplant outcomes is unclear. Of particular interest is ineffective esophageal motility (IEM) and its associated impact on esophageal clearance.

AIM

To assess the relationship between pre-transplant IEM diagnosis and acute rejection after lung transplantation.

METHODS

This was a retrospective cohort study of lung transplant recipients at a tertiary care center between 2007 and 2018. Patients with pre-transplant anti-reflux surgery were excluded. Manometric and reflux diagnoses were recorded from pre-transplant esophageal function testing. Time-to-event analysis using Cox proportional hazards model was applied to evaluate outcome of first episode of acute cellular rejection, defined histologically per International Society of Heart and Lung Transplantation guidelines. Subjects not meeting this endpoint were censored at time of post-transplant anti-reflux surgery, last clinic visit, or death. Fisher’s exact test for binary variables and student’s t-test for continuous variables were performed to assess for differences between groups.

RESULTS

Of 184 subjects (54% men, mean age: 58, follow-up: 443 person-years) met criteria for inclusion. Interstitial pulmonary fibrosis represented the predominant pulmonary diagnosis (41%). During the follow-up period, 60 subjects (33.5%) developed acute rejection. The all-cause mortality was 16.3%. Time-to-event univariate analyses demonstrated significant association between IEM and acute rejection [hazard ratio (HR): 1.984, 95%CI: 1.03-3.30, P = 0.04], confirmed on Kaplan-Meier curve. On multivariable analysis, IEM remained independently associated with acute rejection, even after controlling for potential confounders such as the presence of acid and nonacid reflux (HR: 2.20, 95%CI: 1.18-4.11, P = 0.01). Nonacid reflux was also independently associated with acute rejection on both univariate (HR: 2.16, 95%CI: 1.26-3.72, P = 0.005) and multivariable analyses (HR: 2.10, 95%CI: 1.21-3.64, P = 0.009), adjusting for the presence of IEM.

CONCLUSION

Pre-transplant IEM was associated with acute rejection after transplantation, even after controlling for acid and nonacid reflux. Esophageal motility testing may be considered in lung transplant to predict outcomes.

Foregut Dysmotility in the Lung Transplant Patient

PURPOSE OF REVIEW

To explore the role of upper gastrointestinal disease in the clinical course of lung transplant patients - including its pathophysiology, diagnostic testing, and treatment options.

RECENT FINDINGS

Gastroesophageal reflux disease (GERD) and foregut motility disorders are more prevalent among end-stage lung disease patients and are associated with poorer outcomes in lung transplant recipients. A proposed mechanism is the exposure of the lung allograft to aspirated contents, resulting in inflammation and rejection. Diagnostic tools to assess for these disorders include multichannel intraluminal impedance and pH (MII-pH) testing, high resolution esophageal manometry (HREM), and gastric emptying scintigraphy. The main treatment options are medical management with acid suppressants and/or prokinetic agents and anti-reflux surgery. In particular, data support the use of early anti-reflux surgery to improve outcomes. Newer diagnostic tools such as MII-pH testing and HREM allow for the identification of both acid and non-acid reflux and esophageal motility disorders, respectively. Recent studies have demonstrated that early anti-reflux surgery within six months post-transplant better protects against allograft injury and pulmonary function decline when compared to late surgery. However, further prospective research is needed to evaluate the short and long-term outcomes of these diagnostic approaches and interventions.

Diagnostic differences in the pharmacologic response to cholecystokinin and amyl nitrite in patients with absent contractility vs type I Achalasia

BACKGROUND

Absent esophageal contractility (AC) is distinguished from type 1 achalasia (ACH1) during high-resolution manometry (HRM) on the basis of normal or elevated deglutitive integrated relaxation pressure (IRP) values. However, IRP measurements are subject to pressure recording error. We hypothesized that distinctive responses to pharmacologic provocation using amyl nitrite (AN) and cholecystokinin (CCK) could reliably distinguish AC patients from those with ACH1.

AIM

To compare esophageal response with AN and CCK in a well-defined cohort of ACH1 and AC patients.

METHOD

All available clinical, radiographic, endoscopic, and manometric information in 34 patients with aperistalsis was reviewed to determine the final diagnosis of ACH1 and AC. The differences in response to provocative challenges with the rapid drink challenge (RDC) test and administration of AN and CCK were compared between these two groups.

RESULTS

Eighteen patients were diagnosed with ACH1 and sixteen with AC. While IRP values were significantly higher in ACH1, the standard criterion value misclassified four AC patients as having ACH1 and five ACH1 patients as having AC. IRP values on the RDC did not accurately segregate AC from ACH1, but we were able to identify AN and CCK esophageal motor response criteria that allowed correct classification of ACH1 and AC patients.

CONCLUSIONS

Nearly a quarter of AC and ACH1 patients may be misdiagnosed based on manometric IRP criteria alone. Differences in the esophageal motor responses to AN and CCK have the potential to facilitate the correct diagnosis in these challenging patients.

Esophageal Function Tests are Not Associated with Barium Swallow Findings in Advanced Lung Disease

Gastroesophageal reflux disease and esophageal dysmotility are common in patients with advanced lung disease (ALD) and are associated with worse outcomes. Assessing esophageal function in these patients is relevant for determining pulmonary transplant eligibility and prognosticating post-transplant outcomes. Barium Swallow (BaS) is a non-invasive testing modality often performed as a complement to formal esophageal function tests (EFTs), but its role and clinical utility in this context is unknown. Therefore, we aimed to determine the relationship between BaS and EFTs with high-resolution manometry (HRM) and 24-h ambulatory pH-metry in patients with ALD. We performed a retrospective study of 226 consecutive patients undergoing evaluation for lung transplantation at a single center. All patients underwent EFTs and BaS independent of clinical history or symptoms per institutional protocol. Appropriate statistical tests were performed to evaluate the relationship between EFTs and BaS. Mucosal, reflux and motility findings were categorized. Abnormal motility was reported in 133 (59%) patients by BaS and 99 (44%) by HRM, with a significant difference in the proportions of patients with abnormal studies (p < 0.01). There were 7 (26%) patients with abnormal barium tablet passage who had normal HRM. The sensitivity (35%) and specificity (77%) for detecting pathologic reflux with BaS was poor. Inducibility of reflux and barium column height were not associated with pH-metry results. No clinically significant luminal irregularities were identified. In conclusion, while BaS can non-invasively assess esophageal mucosa, its findings are not associated with EFTs in patients with ALD.

Esophageal contractility increases and gastroesophageal reflux does not worsen after lung transplantation

Gastroesophageal reflux and esophageal dysmotility are common in patients with advanced lung disease and are associated with allograft dysfunction after lung transplantation. The effect of transplantation on reflux and esophageal motility is unclear. The aim of this study was to describe the changes in esophageal function occurring after lung transplantation. A retrospective cohort study was performed on lung transplant candidates evaluated at a tertiary care center between 2015 and 2016. A total of 76 patients who underwent lung transplantation had high-resolution manometry and ambulatory pH-metry before and after transplant. Demographic data, esophageal function testing results, and clinical outcomes such as pulmonary function testing were collected and analyzed using appropriate statistical tests and multivariable regression. Of the 76 patients, 59 (78%) received a bilateral transplant. There was a significant increase in esophageal contractility posttransplant, with an increase in median distal contractile integral from 1470 to 2549 mmHg cm s (P < 0.01). There were 19 patients with Jackhammer esophagus posttransplant, including 15 patients with normal motility pretransplant. Nine patients with ineffective or fragmented peristalsis pretransplant had normal manometry posttransplant. Abnormal pH-metry was observed in 35 (46%) patients pretransplant and 29 (38%) patients posttransplant (P = 0.33). Patients with gastroesophageal reflux disease posttransplant had less improvement in pulmonary function at one year, as measured by forced expiratory volume (P = 0.04). These results demonstrate that esophageal contractility increases significantly after lung transplantation, with an associated change in motility classification. In comparison, gastroesophageal reflux does not worsen, but is associated with worse pulmonary function, posttransplant.

Gastroesophageal reflux symptoms are not sufficient to guide esophageal function testing in lung transplant candidates

Gastroesophageal reflux disease and esophageal dysmotility are prevalent in patients with advanced lung disease and are associated with graft dysfunction following lung transplantation. As a result, many transplant centers perform esophageal function testing as part of the wait-listing process but guidelines for testing in this population are lacking. The aim of this study is to describe whether symptoms of gastroesophageal reflux correlate with abnormal results on pH-metry and high-resolution manometry and can be used to identify those who require testing. We performed a retrospective cohort study of 226 lung transplant candidates referred for high-resolution manometry and pH-metry over a 12-month period in 2015. Demographic data, results of a standard symptom questionnaire and details of esophageal function testing were obtained. Associations between the presence of symptoms and test results were analyzed using Fisher's exact tests and multivariable logistic regression. The most common lung disease diagnosis was interstitial lung disease (N = 131, 58%). Abnormal pH-metry was seen in 116 (51%) patients and the presence of symptoms was significantly associated with an abnormal study (p < 0.01). Dysmotility was found in 98 (43%) patients, with major peristaltic or esophageal outflow disorders in 45 (20%) patients. Symptoms were not correlated with findings on esophageal high-resolution manometry. Fifteen of 25 (60%) asymptomatic patients had an abnormal manometry or pH-metry. These results demonstrate that in patients with advanced lung disease, symptoms of gastroesophageal reflux increase the likelihood of elevated acid exposure on pH-metry but were not associated with dysmotility. Given the proportion of asymptomatic patients with abnormal studies and associated post-transplant risks, a practice of universal high-resolution manometry and pH-metry testing in this population is justifiable.

Chronic obstructive pulmonary disease comorbidities

PURPOSE OF REVIEW

Classic descriptions of chronic obstructive pulmonary disease (COPD) centered on its impact on respiratory function. It is currently recognized that comorbidities contribute to the severity of symptoms and COPD progression. Understanding COPD-comorbidities associations could provide innovative treatment strategies and identify new mechanistic pathways to be targeted.

RECENT FINDINGS

Some comorbidities are clustered with specific COPD phenotypes. There are stronger associations between airway-predominant disease and cardio-metabolic comorbidities, whereas in emphysema-predominant COPD sarcopenia and osteoporosis are frequent. These patterns suggest different inflammatory pathways acting by COPD phenotype. Osteoporosis is a major concern in COPD, particularly among men. Although β-blockers use for cardiac indications in COPD remains low, recent evidence suggests that this medication group could decrease COPD exacerbations. Gastroesophageal reflux is consistently associated with poor COPD outcomes, but mechanisms and impact of treatment are still unclear. Nontraditional comorbid conditions, such as cognitive impairment, anxiety, and depression have significant impact in COPD outcomes.

SUMMARY

Clinicians should screen their COPD patients for the presence of cardiovascular disease, diabetes, osteoporosis, sleep apnea, and sarcopenia, comorbidities for which specific treatments are available and associated with better COPD outcomes. The impact of interventions to treat gastroesophageal reflux disease, anxiety and depression is still to be defined.

Esophageal Dysmotility, Gastro-esophageal Reflux Disease, and Lung Transplantation: What Is the Evidence?

Lung transplantation is an effective and life-prolonging therapy for patients with advanced lung disease (ALD). However, long-term patient survival following lung transplantation is primarily limited by development of an inflammatory and fibrotic process involving the lung allograft known as bronchiolitis obliterans syndrome (BOS). Although the precise cause of BOS remains uncertain and is likely multifactorial, chronic aspiration of gastro-duodenal contents is one possible contributing factor. Multiple small, cross-sectional studies performed over the past two decades have reported a high prevalence of gastro-esophageal reflux disease (GERD) and esophageal dysmotility in the ALD population and several investigations suggest the prevalence may increase following lung transplantation. More recent studies evaluating the direct effect of gastro-duodenal contents on airways have demonstrated a possible biologic link between GERD and BOS. Despite the recent advances in our understanding of BOS, further investigations are needed to establish GERD as a causative factor in its development. This review will discuss the existing literature that has identified an association of GERD with ALD and post-transplant populations, with a focus on recent advances in the field.

Ineffective esophageal motility phenotypes following fundoplication in gastroesophageal reflux disease

BACKGROUND

Ineffective esophageal motility (IEM) is associated with reflux disease, but its natural history is unclear. We evaluated patients undergoing repeat esophageal high resolution manometry (HRM) for symptomatic presentations after antireflux surgery (ARS) to understand the progression of IEM.

METHODS

Patients with repeat HRM after ARS were included. Ineffective esophageal motility was diagnosed if ≥5 sequences had distal contractile integral (DCI) <450 mmHg cm s. Augmentation of DCI following multiple rapid swallows (MRS) was assessed. The esophagogastric junction (EGJ) was interrogated using the EGJ contractile integral (EGJ-CI). Esophageal motor function was compared between patients with and without IEM.

KEY RESULTS

Sixty-eight patients (53.9 ± 1.8 years, 66.2% female) had pre- and post-ARS HRM studies 2.1 ± 0.19 years apart. Esophagogastric junction-CI augmented by a mean of 26.3% following ARS. Four IEM phenotypes were identified: 14.7% had persistent IEM, 8.8% resolved IEM after ARS, 19.1% developed new IEM, and 57.4% had no IEM at any point. Patients with IEM had a lower DCI pre- and post-ARS, lower pre-ARS EGJ CI, and lower pre-ARS-integrated relaxation pressure (p ≤ 0.02 for all comparisons); presenting symptoms and other EGJ metrics were similar (p ≥ 0.08 for all comparisons). The IEM phenotypes could be predicted by MRS DCI response patterns (p = 0.008 across groups); patients with persistent IEM had the least DCI augmentation (p = 0.007 compared to no IEM), while those who resolved IEM had DCI augmentation comparable to no IEM (p = 0.08).

CONCLUSIONS & INFERENCES

Distinct phenotypes of IEM exist among symptomatic reflux patients following ARS. Provocative testing with MRS may help identify these phenotypes pre-ARS.

Lung Transplantation for Scleroderma-related Lung Disease

Lung transplantation for scleroderma-related lung disease is controversial due to extra-pulmonary organ involvement that may threaten allograft and patient survival after transplant surgery. Despite concerns, several lung transplant programs do offer lung transplantation to patients with scleroderma-related lung disease. In this review, we evaluate the scleroderma-related extra-pulmonary organ involvement that may result in poorer outcomes after lung transplantation as well as the existing evidence on survival, freedom from bronchiolitis obliterans syndrome (BOS), and other important clinical outcomes after lung transplantation. Among the nine studies reviewed, comprising 226 subjects, survival and freedom from BOS appears to be similar for subjects undergoing lung transplantation for scleroderma compared to non-scleroderma lung diseases. Although scleroderma is a systemic disease with several unique potential threats to allograft and patient survival, lung transplantation appears to be a reasonable intervention for this patient population.