The characteristics of upper lobe-origin hemoptysis: analysis based on 31 patients
Highlight box
Key findings
• The special subtype of hemoptysis, named as upper lobe-origin hemoptysis (ULOH), could be succeeded ceasing the bleeding after bronchial artery embolization (BAE) procedures. No patient experienced recurrence after a median of 24 months follow-up period, and the lung structure and function could be restored to normal.
What is known and what is new?
• BAE has been posed as an effective treatment for these hemoptysis patients.
• These non-life-threatening hemoptysis patients, who do not display either suspicious culprit arteries or pulmonary diseases, should be termed as a special subtype. BAE procedure could be an option and effective for these patients.
What is the implication, and what should change now?
• For these ULOH patients, who experienced hemoptysis relapse after standard conservative treatment, BAE procedure should be taken into consideration.
Introduction
Hemoptysis, as a significant clinical symptom, is closely associated with various respiratory diseases, including bronchiectasis, tuberculosis sequalae, pulmonary infection, and lung cancer (1-3). Given that the potential causes of hemoptysis vary in both pathophysiological mechanisms and imaging manifestations, bronchial artery embolization (BAE) has been posed as an effective treatment for these patients (4-6). And preoperative computed tomography (CT) angiography (CTA) is routinely performed to reveal abnormalities of lung structure, bleeding location, culprit vessels, which facilitates the BAE procedures (7,8).
Conversely, a small proportion of non-life-threatening hemoptysis patients do not display either suspicious culprit arteries or pulmonary diseases, whether to perform embolization immediately requires multidisciplinary discussion for making a decision. In fact, these patients experience varying episodes of relapse after 72 hours of standard conservative treatment (e.g., airway management, hemostatic drugs, antibiotics, etc.), which is mainly manifested as (I) persistent or recurrent hemoptysis; (II) uncontrollable symptom impact. We were trying to unify the clinical characteristics of these patients, especially summarizing as relatively consistent imaging signs: (I) hemorrhage of alveoli was confined to the upper lobes; (II) the diameter of all bronchial arteries was no more than 2.0 mm. We define it as “upper lobe-origin hemoptysis (ULOH)”. This situation presents a clinical dilemma: unexplained etiology of hemoptysis and in corresponding of the absence of abnormal bronchial arteries, which raises clinical concerns about the necessity and efficacy of embolization.
Here, as a preliminary exploration, we continuously collected a case series of 31 patients who benefited from BAE procedure in our single institution, and we documented the clinical symptoms, imaging features, details on angiography, and long-term outcomes after respiratory rehabilitation. The aim was to help to gain deeper insights into the characteristics of these patients and facilitate timely embolization procedure in clinical practice, thereby improving clinical outcomes. We present this article in accordance with the STROBE reporting checklist (available at https://jtd.amegroups.com/article/view/10.21037/jtd-2025-1872/rc).
Methods
This study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Ethics Committee of The First Affiliated Hospital with Nanjing Medical University Institutional Review Board (No. 2025-SR-07103). Written informed consent was waived due to its retrospective study nature.
Study participants
From April 2019 to March 2024, the medical records of 482 non-cancer related hemoptysis patients who underwent arterial embolization were reviewed. According to our initial concept of ULOH, a total of 31 patients (6.4%) met the criteria for enrollment.
Conservative treatment
Vital sign monitoring, correction of hypoxemia, hemostasis medicine, nebulized inhalation, and antibiotic therapy were standard conservative treatment for each case. There was a multidisciplinary team for hemoptysis management in the First Affiliated Hospital with Nanjing Medical University, including the Emergency, Respiratory, Radiology, Interventional Radiology, Chest Surgery, and Rehabilitation Departments. Antihemorrhagic drugs included pituitrin, phentolamine and cibachromes sodium sulphonate. As differential diagnosis, laboratory test including complete blood count, C-reactive protein, T-spot, antinuclear antibody, anti-neutrophil cytoplasmic antibody, and anti-glomerular basement membrane antibody, etc., were tested.
Arterial embolization procedures
After confirming the absence of BAE contraindications via multidisciplinary discussion, the embolization procedures were performed. Contraindications excluded included absolute conditions (severe coagulation disorders, critical renal/hepatic insufficiency precluding contrast media use, irreversible distal tissue ischemia) and relative conditions (uncorrectable severe hypertension, severe bronchial artery tortuosity or non-selectable vessels (1-4). Angiography was performed by a 5 F catheter (Cobra, RLG, Cook Medical, Bloomington, USA) via the femoral artery approach. Then super-selective catheterization was performed by using a 2.4 F (Maestro, Merit, South Jordan, USA) or 1.7 F (Echelon10, EV3, Irvine, USA) microcatheter. As mentioned above, systemic-pulmonary shunt (SPS) at bilateral apexes during angiography were the main abnormal angiographic signs. Embolization materials included microspheres (300–500 µm; 500–700 µm, Merit, USA), glue (GLUBRAN 2, Viareggio, Italy) at a concentration of 5%, and gelatin sponge particles (350–560 µm, Alicon, Nanjing, China).
Rehabilitation, assessment and follow-up
After bleeding ceased over 72 hours, respiratory rehabilitation was prescribed (the detail of respiratory rehabilitation protocol was provided in the Appendix 1). Chest CT scan was performed at one month after procedure. Then patient took 6 months home-based rehabilitation, and followed integrated analysis was assessed by dual-energy CT (DECT) (the detail of DECT protocol was provided in the Appendix 1). Meanwhile, clinical features included age, sex, smoking history, hemoptysis volume, the time of conservative treatment and episodes of relapse, location of affected segments, diameter of culprit artery, angiographic findings, embolization materials and outcomes after procedures were recorded. Procedure-related complications were graded by the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) classification (7): Grade 1/2 (minor or moderate complications), Grade 3/4 (severe or critical complications, meaning events requiring invasive or surgical intervention or leading to temporary organ dysfunction resolving, severe events causing permanent organ damage, life-threatening conditions like spinal cord ischemia, or mortality). The severity of smoking was classified into mild (1–10 cigarettes/day and have smoked for no more than 5 years), moderate (11–20 cigarettes/day or smoking for more than 5 years but less than 10 years) or heavy smokers (>20 cigarettes/day or smoking for more than 10 years) (8). The end date of follow-up was June, 2025. Recurrence was defined as relapse requiring unscheduled admission for hemoptysis, including conservative treatment, BAE, surgical treatment, or death (6).
Statistical analysis
Demographic data were collected for each patient, including, age, sex, amount of hemoptysis, etc. Quantitative variables are presented as median and range, and qualitative variables by counts and percentages. Statistical analysis was performed by using Statistical Package for the Social Sciences (version 25.0, New York, USA). Descriptive statistics were used to analyze the outcomes.
Results
Patients’ characteristics
The patients’ characteristics are detailed in Table 1. The median age of the patients was 49.0 years (ranging from 26 to 66 years). Twenty-eight patients (90.3%) were male, and 22 cases (71.0%) were heavy smokers. All patients experienced 1–3 times mild or moderate hemoptysis relapse after differ durations conservative treatment. The level of C-reactive protein was localized within normal range, the results of T-spot was negative in each case and the test results for autoimmune disease markers were also negative in each case.
Table 1
| No. | Age (years) | Sex | Amount of hemoptysis (mL/d) | Conservative treatment time (days) | Smokers† | Ground-glass opacity in the upper lobes on CT | White blood cell (109/L) | Neutrophils (%) | C-reactive protein (mg/L) | Culprit vessel diameter (mm) | Follow-up period (months) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 26 | Male | 40 | 10 | Moderate | Right (S1) | 7.51 | 75.20 | <5 | 1.8 (R); 1.1 (L) | 66 |
| 2 | 46 | Male | 100 | 8 | Heavy | Right (S1+S2) | 7.73 | 66.50 | <5 | 2.0 (R); 1.4 (L) | 63 |
| 3 | 51 | Male | 100 | 5 | Heavy | Right (S1) | 6.25 | 54.70 | <5 | 2.0 (R); 1.0 (L) | 56 |
| 4 | 47 | Male | 80 | 30 | Heavy | Right (S1) | 8.26 | 86.40 | 6.28 | 1.4 (R); 1.0 (L) | 53 |
| 5 | 46 | Male | 30 | 30 | Heavy | Left (S3) | 6.40 | 64.20 | 6.10 | 1.5 (R); 1.9 (L) | 47 |
| 6 | 64 | Male | 10 | 30 | Heavy | Right (S2) | 6.95 | 57.25 | <5 | 1.5 (R); 1.3 (L) | 49 |
| 7 | 56 | Female | 50 | 10 | NA | Right (S1) | 4.47 | 83.00 | <5 | 1.7 (R); 1.5 (L) | 31 |
| 8 | 64 | Male | 30 | 14 | Heavy | Right (S1) | 9.35 | 47.30 | 8.90 | 2.0 (R); 1.5 (L) | 28 |
| 9 | 57 | Male | 80 | 5 | Heavy | Right (S1) | 10.30 | 80.40 | 6.50 | 2.0 (R); 0.8 (L) | 25 |
| 10 | 58 | Male | 100 | 30 | Heavy | Left (S3) | 6.15 | 58.50 | <5 | 1.0 (R); 1.7 (L) | 25 |
| 11 | 52 | Male | 20 | 30 | Heavy | Right (S1) | 12.98 | 69.50 | <5 | 2.0 (R); 1.5 (L) | 25 |
| 12 | 64 | Male | 150 | 6 | NA | Right (S3) | 12.16 | 79.00 | <5 | 1.9 (R); 1.7 (L) | 25 |
| 13 | 58 | Male | 50 | 11 | Heavy | Left (S1+S2) | 5.44 | 66.80 | 7.50 | 1.5 (R); 1.9 (L) | 19 |
| 14 | 36 | Male | 10 | 15 | Heavy | Right (S1) | 10.23 | 76.30 | <5 | 1.5 (R); 1.5 (L) | 19 |
| 15 | 28 | Female | 10 | >30 | NA | Left (S1) | 6.84 | 60.90 | <5 | 1.5 (R); 1.0 (L) | 25 |
| 16 | 58 | Male | 40 | 11 | Heavy | Right (S1) | 5.58 | 69.00 | <5 | 2.0 (R); 1.4 (L) | 24 |
| 17 | 55 | Male | 200 | 6 | Heavy | Right (S1) | 5.08 | 47.00 | <5 | 1.5 (R); 1.1 (L) | 21 |
| 18 | 50 | Male | 30 | 9 | Heavy | Right (S2) | 9.19 | 73.60 | <5 | 1.8 (R); 1.0 (L) | 20 |
| 19 | 53 | Male | 150 | 8 | Heavy | Right (S1) | 11.68 | 88.10 | <5 | 2.0 (R); 1.3 (L) | 20 |
| 20 | 30 | Male | 30 | 13 | Heavy | Right (S1) | 8.84 | 71.50 | <5 | 1.8 (R); 1.2 (R); 1.9 (L) | 20 |
| 21 | 49 | Male | 20 | 7 | Heavy | Left (S1) | 8.37 | 64.70 | <5 | 1.9 (R); 1.9 (L) | 18 |
| 22 | 45 | Male | 30 | 13 | Moderate | Right (S2) | 6.24 | 76.70 | <5 | 2.0 (R); 1.5 (L) | 18 |
| 23 | 34 | Male | 150 | 6 | Heavy | Left (S1) | 7.38 | 74.10 | <5 | 1.5 (R); 1.8 (L) | 15 |
| 24 | 66 | Female | 200 | 10 | NA | Left (S1+S2) | 7.72 | 79.90 | <5 | 1.9 (R); 1.8 (L) | 15 |
| 25 | 49 | Male | 60 | >30 | Heavy | Right (S1) | 8.96 | 67.60 | <5 | 2.0 (R); 1.4 (L) | 16 |
| 26 | 51 | Male | 200 | 5 | NA | Right (S1) | 10.97 | 79.50 | <5 | 1.1 (R); 1.5 (L) | 17 |
| 27 | 63 | Male | 5 | >30 | Heavy | Right (S2) | 6.68 | 71.20 | 5.83 | 1.7 (R); 1.5 (L); 1.0 (L) | 13 |
| 28 | 59 | Male | 150 | 7 | NA | Right (S2) | 5.45 | 86.40 | <5 | 1.9 (R); 1.7 (L) | 23 |
| 29 | 34 | Male | 20 | >30 | Moderate | Right (S1) | 9.01 | 68.20 | <5 | 1.0 (R); 1.3 (L) | 24 |
| 30 | 57 | Male | 100 | 10 | Heavy | Left (S1+S2) | 6.38 | 66.20 | <5 | 1.9 (R); 2.0 (L) | 24 |
| 31 | 34 | Male | 80 | >30 | Heavy | Right (S1) | 7.98 | 72.50 | <5 | 1.3 (R); 1.5 (L); 1.1 (L) | 12 |
†, mild smokers: smoke less than 10 cigarettes per day and have smoked for no more than 5 years; moderate smokers: smoking 10–20 cigarettes per day or smoking for more than 5 years but less than 10 years; heavy smokers: smoking more than 20 cigarettes per day or smoking for more than 10 years. CT, computed tomography; L, left; NA, not applicable; R, right.
Angiographic findings and embolization
Ground-glass opacity and alveolar infiltrate was localized at the unilateral upper lobe of lung in each case. Sixty-five bronchial arteries (32 right and 33 left) were identified in all patients. The range of culprit bronchial arteries’ diameters on CTA was 1.0 to 2.0 mm. During bronchial artery angiography, SPS were identified and coincide with the CT abnormal site in each patient; additionally, SPS were also observed on mirror location of contralateral upper lobe. During the procedures, no additional culprit vessel was identified. Twenty-one patients were embolized with microspheres (300–500 µm) and 9 cases were microspheres (500–700 µm), while, here, gelatin sponge particles, as adjunctive embolic agent, played a role in assisting enhanced embolization. Contrast agent extravasation was the direct bleeding sign in one case and embolized with glue. Ten (32.3%) patients reported mild or moderate chest discomfort after procedures and recovered with conservative treatment.
Rehabilitation and follow-up assessments
Bleeding ceased within 24 hours after embolization. Then 72 hours later, respiratory rehabilitation initiated. And the followed integrated analysis of DECT showed that structure and perfusion were normal. Two representative figures are shown in Figures 1,2. During the median follow-up period of 24 months, no patient experienced recurrent hemoptysis.
Discussion
In general, the clinical characteristics included: (I) unexplained etiology of hemoptysis; (II) varying episodes of non-life-threatening hemoptysis relapse after standard conservative treatment; (III) laboratory tests showed no hints of lung infections, tuberculosis, aspergillosis, coagulation dysfunction, etc.; (IV) hemorrhage of alveoli was confined to the upper lobes and the diameter of all bronchial arteries was no more than 2.0 mm on CT angiography; (V) symmetrical SPS at bilateral apexes during bronchial artery angiography; (VI) after BAE procedure, lung structure and function could be restored to normal. Here, 6.4% (31/482) of cases were reclassified as ULOH in our clinical practices. Notably, all the patients succeeded ceasing the bleeding after procedures, and no patient experienced recurrence after a median of 24 months follow-up period. Meanwhile, we preliminary explored the introduction of respiratory rehabilitation after BAE procedure, and dual energy CT evaluation also indicated that these patients could recover to normal structure and function completely.
In fact, nearly 25% of patients remain classified as cryptogenic hemoptysis (9-11). Among them, 6.4% could be reclassified as ULOH subgroup in this study. In details of clinical characteristics, ULOH population showed clearly different manifestations: (I) the hemorrhage of alveoli was confined to the upper lobes. In contrast, the bleeding sites in cryptogenic hemoptysis were scattered or involved multiple lung lobes (12,13); (II) the diameters of the bronchial arteries were all no more than 2 mm and there were no ectopic bronchial arteries or nonbronchial systemic blood supply branches, in contrast to the general cryptogenic hemoptysis patients, bronchial arterial enlargement was found in 62.9–83%, and varying number of patients had aberrant bronchial artery or nonbronchial systemic artery (11-13); (III) bronchial artery angiography revealed SPS at the bilateral apexes in each patient. By comparison, SPS existing in varying rates of patients (5.7%, 23%, and 80%), which were reported differ in the research about cryptogenic hemoptysis (11-13). However, the specific mechanism of SPS occurrence is not yet clear. In the study, 71.0% of male patients were heavy smokers. As reported in previous studies (14), smoking may induce inflammation of the bronchus, and lead to vascular remodeling, gradually resulting in SPS. Additionally, the special anatomical location and hemodynamic characteristics may also cause SPS at the lung apex, which was also reported that a well-known predominant or exclusive distribution of smoking-induced inflammatory changed in the upper lung in previous study (13). Thus, in numerical incidence and clinical characteristics terms, ULOH could be the distinct subtype of hemoptysis patients. By contrast, different proportions of patients in previous studies (4) still failed to achieve complet cessation of hemoptysis (15%) or experienced recurrent hemoptysis during a median 2-year follow-up period (3–4%) (11-13,15). Thus, the subgroup of cryptogenic hemoptysis shares a common risk factor with patients in whom hemoptysis is explained by ULOH.
For these patients, BAE was proposed as the first-line treatment method (6,7,11,16). And particulate agents were the standard embolic material in BAE procedure (7,17,18). In our study, embosphere particles combined with gelatin sponge particles were the main materials, which could enhance the embolization effect and reduce the possibility of vessel re-communication (19). Notably, there was no recurrence during the follow-up period, which also indirectly suggests that BAE as a procedure, may not be preferred but proven effective choice. After bleeding cessation, patients were prescribed with respiratory rehabilitation. Combined with 6-month standardized respiratory rehabilitation, DECT clearly shows the pulmonary perfusion imaging, confirming the significant efficacy of this comprehensive treatment plan at both the structural and functional levels. Respiratory rehabilitation, as a key link in the management of respiratory system diseases, not only improves lung function but also enhances the quality of life of patients (20,21). The application of dual energy CT provides an objective basis for the formulation of individualized rehabilitation plans.
Several limitations of the present study should be acknowledged. First, this was a retrospective study with its inherent limitations. Second, bronchoscopy could help to understand the mechanism of hemoptysis (22), but in our study cohort, 7 out of 31 patients underwent bronchoscopy (22.6%), and the related bronchoscopy findings and bronchoalveolar lavage fluid analysis assessment showed negative results. However, we still need to extent the proportion for bronchoscopy to clarify the possible etiology of hemoptysis. Third, the explanation of bilateral SPS remains unclear, the study speculated that smoking may contribute to SPS, but there is a significant gender imbalance in the study population. In the future, we will assess the impact of gender-related indicators such as hormone levels on the disease (23).
Conclusions
In conclusion, patients with ULOH presented as normal diameter of bronchial arteries and symmetrical characteristic of SPS at bilateral apexes during angiography. Moreover, after BAE procedure, these patients achieved complete recovery in both structure and function, indicating that BAE is a safe and effective treatment method for patients with ULOH.
Acknowledgments
None
Footnote
Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2025-1872/rc
Data Sharing Statement: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2025-1872/dss
Peer Review File: Available at https://jtd.amegroups.com/article/view/10.21037/jtd-2025-1872/prf
Funding: None.
Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-2025-1872/coif). The authors have no conflicts of interest to declare.
Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. This study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by the Ethics Committee of The First Affiliated Hospital with Nanjing Medical University Institutional Review Board (No. 2025-SR-07103). Written informed consent was waived due to its retrospective study nature.
Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.
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