Endobronchial changes in chronic pulmonary venous hypertension

A case report of life-threatening hemothorax after percutaneous lung biopsy successfully managed with embolization

CT-guided lung biopsy is a widely used procedure for tissue identification. The complications are divided into minor and major with the latter being described as low rate. Hemothorax is reported at a rate of 0.092% and predominantly results from the injury of intercostals or internal mammary arteries. We present the case of 81-year old woman with a right upper lobe mass referred for a CT-guided biopsy. Four hours after the procedure, rapid deterioration of patient's status was observed. A massive hemothorax was reported due to the transection of an intratumoral pulmonary branch. The following management involved successful emergent embolization of the injured branch of the pulmonary artery using a combination of coils and gel foam. One of the theories possibly explaining this extremely rare complication involves the possibility of underlying pulmonary hypertension.

Risk of bleeding associated with transbronchial biopsy using flexible bronchoscopy in patients with echocardiographic or chest CT evidence of pulmonary hypertension

Background

Endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB) facilitates the diagnosis of various respiratory diseases. The safety of performing EBUS-guided TBB in patients with a finding of pulmonary hypertension (PH) is controversial. Little is known about the relationship between the risk of bleeding associated with EBUS-guided TBB in the presence of PH suspected on echocardiography or chest CT.

Methods

To assess the risk of bleeding associated with EBUS-guided TBB in patients with presumed PH per echocardiography or chest CT, we retrospectively reviewed the medical records of 314 consecutive patients who underwent EBUS-guided TBB using a guide sheath (GS), as well as echocardiography and chest CT. Bleeding complication was defined as over one minute of suctioning; repeated wedging of the bronchoscope; instillation of cold saline, diluted vasoactive substances, or thrombin due to persistent bleeding. Findings of suspected PH were defined as peak tricuspid regurgitation velocity (TRV) > 2.8 m/s on echocardiography or pulmonary artery to aorta ratio (PA:A ratio) > 0.9 on chest CT.

Results

In total, 35 (11.1%) patients developed bleeding, and all cases were managed safely. Furthermore, 17 (5.4%) and 59 (18.8%) patients were suspected to have PH based on echocardiography and chest CT, respectively. Among the patients suspected to have PH on echocardiography, five (5/17 = 29.4%) patients developed bleeding. Among the patients suspected to have PH on chest CT, 11 (11/59 = 18.6%) patients developed bleeding. Univariate analysis revealed that long diameter (≥ 30 mm) of the lesion, lesion location (the biopsy site was inner than the segmental bronchus), bronchoscopic diagnosis of malignancy, and additional biopsy were potential predictive factors for bleeding. The finding of suspected PH on echocardiography correlated significantly with bleeding (p = 0.03). On multivariate analysis, long diameter (≥ 30 mm) of the lesion (p = .021) and findings of suspected PH on echocardiography (p = .049) were significantly associated with bleeding.

Conclusion

All cases of bleeding in the present study were managed safely. The risk of bleeding is moderately elevated when PH is suspected by echocardiography in patients undergoing EBUS-guided TBB using a GS.

Transbronchial Cryobiopsy in Interstitial Lung Diseases: State-of-the-Art Review for the Interventional Pulmonologist

Interstitial lung diseases are a heterogenous group of disorders that are often difficult to diagnose precisely. Clinical, laboratory, radiographic, and histologic information may be needed to arrive at the correct diagnosis. The multidisciplinary discussion has been proven to be useful in this patient group. Transbronchial cryobiopsy has become a popular method for obtaining tissue samples. Over the course of the last decade, there has been a significant amount of research assessing the feasibility, safety, and diagnostic endpoints of transbronchial cryobiopsy in patients with interstitial lung disease. Data continues to mount to support its use, which has been reflected in guidelines and expert panel reports. Patient selection, procedural performance, and appropriate specimen handling are critical factors for success. A coordinated approach by pulmonologists with expertise in interstitial lung diseases, interventional pulmonologists, and thoracic pathologists is essential. In this evidence-based narrative review, we address transbronchial cryobiopsies from these three distinct perspectives. In addition, the current literature was used to address nine common procedural questions.

Pulmonary Hypertension and Transbronchial Lung Biopsy: Does It Increase the Risk of Hemorrhage?

Background Bronchoscopy with transbronchial lung biopsy (TBLB) is commonly used as a diagnostic tool for pulmonary disease. Hemorrhage is a major complication of TBLB. While pulmonary hypertension (PH) is considered a risk factor, evidence supporting this is limited. In this study, we compare complications of TBLB in patients with PH to those without PH. Material and methods We performed a retrospective review of patients who underwent TBLB in our institution from January 2010 to May 2016. PH and non-PH groups were compared with respect to patient demographics, biopsy guidance, number of lobes biopsied (single or multiple), positive pressure ventilation, pre- and post-procedure diagnoses, and complications. Complications were defined as major hemorrhage, prolonged intubation, and reintubation within 72 hours from TBLB. Results The PH group had 45 patients with a mean age of 71 ± 14 years, and the non-PH group had 349 patients with a mean age of 63 ± 14 years. There were no significant differences with regards to gender, pre-procedure anticoagulation and antiplatelet agents, biopsy guidance, or number of lobes biopsied (p > 0.371). There was no significant difference in the occurrence of major hemorrhage between the two groups (p = 0.491). Prolonged intubation occurred more frequently in the PH group (p = 0.007). Conclusions There appears to be no increased risk of post-procedure hemorrhage with TBLB in patients with mild PH. There is, however, an increased risk of post-procedure prolonged intubation in these patients.

Safety of diagnostic flexible bronchoscopy in patients with echocardiographic evidence of pulmonary hypertension

BACKGROUND

The presence of pulmonary hypertension (PH) and treatment with anticoagulant agents could potentially increase the risk for bleeding/hemodynamic complications associated with bronchoscopic procedures. The aim of this study was to assess the safety of diagnostic flexible bronchoscopy (FB) in patients with PH.

METHODS

A retrospective review of clinical records of patients with echocardiographic evidence of PH (right ventricular systolic pressure [RVSP] > 40 mm Hg) who underwent diagnostic FB between 2004 and 2016 at a single facility in Japan was conducted. Patients with no clinical evidence suggestive of PH who underwent FB during the same period were enrolled as a pairwise-matched control group; factors used in matching included age, sex, and performed procedures.

RESULTS

Overall, there were 45 patients in the PH group and 90 patients in the control group. Six (13%) patients in the PH group had severe PH (RVSP > 61 mm Hg). Forceps biopsies and transbronchial needle aspirations were performed in 62% and 13% of patients, respectively, in the PH group, and 58% and 13% of patients, respectively, in the control group. The total incidence of bleeding during FB was not significantly different between the two groups (18% versus 16%; p = 0.742). Vital signs recorded 2 h after FB were also not significantly different between the two groups. There were no episodes of cardiac arrhythmias or deaths associated with the FB procedures.

CONCLUSIONS

The data suggest that diagnostic FB procedures can be performed safely in patients with echocardiographic evidence of PH.

Pulmonary veno-occlusive disease and pulmonary capillary hemangiomatosis

Pulmonary veno-occlusive disease is a rare cause of pulmonary hypertension which is part, together with pulmonary capillary hemangiomatosis, of the special designation (subgroup 1') within pulmonary hypertension group 1 in the latest classification of the pulmonary hypertension World Symposium. Recent discovery that gene mutations in eukaryotic translation initiation factor 2 alpha kinase 4 (EIF2AK4) are responsible for inherited forms of pulmonary veno-occlusive disease has changed the role of genetic testing, acquiring relevant importance in the diagnosis of these patients. Despite the advances in genetic, cellular and molecular basis knowledge in the last decade, pulmonary veno-occlusive disease remains as a rare aetiology of pulmonary hypertension without any effective medical treatment approved and poor outcomes. This document aims to review the advances occurred in the understanding of pulmonary veno-occlusive disease in the last years.

Distinguishing Bronchoscopic Changes of Mitral Stenosis From Carcinoma In Situ With Narrow Band Imaging

A 75-year-old woman presented with minor hemoptysis. Past history included atrial fibrillation and rheumatic mitral stenosis. Bronchoscopy revealed a striking abnormality of widespread dilated mucosal and submucosal vessels. Initially the concern was whether there was widespread endobronchial malignancy; however, narrow band imaging (NBI) demonstrated the symmetrical uniform nature of the vessels. In addition, there was a focal area of in situ carcinoma with classic NBI features of malignancy. Following external-beam radiation therapy, NBI features had dramatically changed in the treated area which was now biopsy negative. The case highlights the utility of NBI in identifying endobronchial microvessel appearance even where there are widespread nonmalignant vessel changes in the bronchial mucosa.

Vessels of the Central Airways: A Bronchoscopic Perspective

Blood supply of the tracheobronchial tree is derived from a dual system involving pulmonary and bronchial circulation. Various primary and secondary abnormalities of central airway vasculature can present with patterns that are distinct during bronchoscopy. These patterns maybe visualized during bronchoscopic evaluation of a patient with hemoptysis or as an incidental finding during an airway examination for other indications. Thorough knowledge of airway vasculature abnormalities and recognition of possible underlying pathophysiology is vital for the bronchoscopist. This review is a comprehensive description of vascular anatomy of the airway and the different vascular abnormalities that can be encountered during bronchoscopy.

Increased hypoxemia in patients with COPD and pulmonary hypertension undergoing bronchoscopy with biopsy

BACKGROUND AND OBJECTIVE

Patients with pulmonary hypertension (PH) are considered to be at risk for complications associated with flexible bronchoscopy (FB), but data concerning the degree of PH are often lacking. We investigated whether COPD patients with PH who undergo bronchoscopy are at greater risk for complications.

METHODS

This prospective study included 207 consecutive COPD patients undergoing FB. All underwent an echo-Doppler to evaluate pulmonary artery pressure on the day of the bronchoscopy procedure. Pulmonologists were blinded to the echocardiogram results.

RESULTS

A total of 167 patients (80.7%) had normal pulmonary pressure. The remaining 40 patients (19.3%) had PH: 27 (13.0%) mild, eight (3.9%) moderate, and five (2.4%) severe. Noninvasive hemodynamic parameters between groups before and after FB were similar. Two patients with normal pulmonary pressure developed supraventricular tachycardia. None developed hemodynamically significant dysrhythmia. Bleeding episodes between groups in bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB) did not differ. PH patients who underwent BAL and TBB had decreased O2 saturation during the procedure compared with the non-PH group (23.5% vs 6.9%, P=0.033). No deaths were attributable to FB.

CONCLUSION

PH is common among COPD patients undergoing FB. PH patients undergoing BAL and TBB are at higher risk of decreased O2 saturation than those without PH. Further studies should assess the risk among COPD patients with moderate-to-severe PH.

Subepithelial microvasculature in large airways observed by high-magnification bronchovideoscope

BACKGROUND

The bronchial vasculature serves important functions and is modified in a variety of pulmonary and airway diseases. The remarkable ability of the bronchial vasculature to undergo remodeling has implications for disease pathogenesis. However, there is very little information on normal bronchial circulation.

OBJECTIVES

The aim of this study was to obtain information on bronchial microvessels in large airways using a high-magnification bronchovideoscope.

METHODS AND PATIENTS

Recently, we developed a high-magnification bronchovideoscope (XBF-200HM3 [side-viewing type]) in cooperation with Olympus Medical Systems. This bronchovideoscope can provide information on the bronchial mucosa with a maximum magnification of 110 times. Between August 2000 and July 2004, 26 patients without abnormalities in the large airways were enrolled into this study. Patients underwent conventional bronchoscopy and subsequent bronchoscopy with the high-magnification bronchovideoscope. After the bronchoscopic examination, we calculated the vessel area ratios and hemoglobin indexes of images made with the high-magnification bronchovideoscope by using appropriate software. In addition, we compared the findings obtained with the high-magnification bronchovideoscope of the 26 subjects with microscopic findings of autopsied tracheas of two patients without abnormalities.

RESULTS

Many ramifying subepithelial microvessels of large airways were mainly observed in intercartilage and membranous portions, whereas only a few microvessels were seen in cartilage portions. Histologically, these subepithelial microvessels were thought to be distributed within approximately 800 and 500 microm beneath the surface of the intercartilage portions and membranous portions, respectively. Vessel area ratios of the intercartilage portions were significantly higher than those of the cartilage and membranous portions. The hemoglobin indexes of the intercartilage portions were significantly higher than those of the cartilage and membranous portions, and these indexes were also significantly higher in the membranous portion than in the cartilage portion.

CONCLUSIONS

A dense concentration of subepithelial microvessels was mainly observed in the intercartilage portion, indicating an increase in submucosal circulation. This high-magnification bronchovideoscope is a useful tool for observing and evaluating the subepithelial microvessels in large airways.

Pulmonary veins and bronchial vessels undergo remodeling in sustained pulmonary hypertension induced by continuous air embolization into sheep

While it is well known that chronic pulmonary hypertension is accompanied by characteristic structural changes in the pulmonary arteries, it is becoming increasingly apparent that the remodeling process also involves the venous side of the circulation. The present paper utilizes a sheep model of sustained pulmonary hypertension induced by continuous air embolization (CAE) into the pulmonary arterial circulation to examine the structure of the pulmonary veins and bronchial vasculature. Morphometric techniques were applied to the pulmonary veins and bronchial vessels following distension of the venous circulation with a barium-sulfate gelatin mixture; this route of filling also resulted in distension of the bronchial vessels. Four and 12 days of CAE resulted in a significant increase in the proportion of muscular pulmonary veins (e.g., percent muscular veins < 75 microns following 12 days CAE = 17.7 +/- 6.9; controls = 0), an approximate doubling in percent venous medial thickness, and a 50% reduction in number of barium-filled peripheral vessels. Examination of the bronchial circulation revealed a striking increase in volume due both to a 50% increase in vessel diameter and a threefold increase in number of small vessels (p < .05). The authors conclude that CAE-induced chronic pulmonary hypertension is associated with remodeling of both the pulmonary veins and bronchial circulation as well as the pulmonary arteries. The mechanisms for these structural alterations are not certain, but may include local release of vasoactive and inflammatory mediators and an increase in bronchopulmonary anastomoses.

Systemic to pulmonary bronchial blood flow in heart failure

STUDY OBJECTIVE

The aim of this study was to measure systemic to pulmonary blood flow from bronchial circulation (Qbr[s-p]) in patients with heart failure.

DESIGN

In the absence of pulmonary and coronary flows, Qbr(s-p) is the volume of blood accumulating in the left side of the heart; Qbr(s-p) was measured during total cardiopulmonary bypass for coronary artery surgery; bronchial blood was vented through a cannula introduced into the left side of the heart and its volume was measured.

PATIENTS

Patients were subdivided according to the presence for more than 6 months (group 1, n = 6) or less than 2 months (group 2, n = 7), or the absence of heart failure (group 2, n = 15).

MEASUREMENTS AND RESULTS

Qbr(s-p) was 89 +/- 18* mL/min, 27 +/- 3, 22 +/- 2, in groups 1, 2, and 3, respectively (* = p < 0.01 group 1 vs groups 2 and 3). During total cardiopulmonary bypass, pulmonary venous pressure approximates atmospheric pressure and no differences between groups were observed in systemic artery pressure, extracorporeal circulation pump flow, and airway pressure. Therefore, vascular resistance through the bronchial vessels draining into the pulmonary circulation is reduced in patients with heart failure for more than 6 months (group 1).

CONCLUSIONS

During total cardiopulmonary bypass, Qbr(s-p) is increased in patients with chronic heart failure. Since with elevated pulmonary vascular pressure blood flow through Qbr(s-p) vessels is from the pulmonary to the systemic circulation, the lower resistance observed in group 1 suggests that bronchial vessels might contribute to reduced lung fluid overload in patients with chronic heart failure.

Abnormalities of pulmonary function in congestive heart failure

The heart and the lungs are strictly integrated both mechanically and functionally in what is now called the cardiopulmonary unit [1-4]. As a consequence, an abnormality of either component of this cardiopulmonary unit quickly alters the physiology of the other. In fact, right ventricular dysfunction and failure secondary to lung disease (i.e. cor pulmonale) are well known; on the other hand the impairment of lung function induced by left heart failure seems obvious, but the knowledge of its pathophysiological mechanism is still incomplete. In this article we will review the structural and functional changes induced by congestive heart failure on the lungs, their relation to the hemodynamic abnormalities and response to therapeutic interventions.

Massive haemoptysis caused by congenital absence of a segment of inferior vena cava

A patient with congenital absence of a part of the inferior vena cava is described. This resulted in spontaneous rupture of a bronchial vein leading to massive haemoptysis.