Pulmonary Endarterectomy in Patients With Myeloproliferative Neoplasms

Clonal Hematopoiesis of Indeterminate Potential in Chronic Thromboembolic Pulmonary Hypertension: A Multicenter Study

BACKGROUND

The pathogenesis of chronic thromboembolic pulmonary hypertension (CTEPH) is multifactorial and growing evidence has indicated that hematological disorders are involved. Clonal hematopoiesis of indeterminate potential (CHIP) has recently been associated with an increased risk of both hematological malignancies and cardiovascular diseases. However, the prevalence and clinical relevance of CHIP in patients with CTEPH remains unclear.

METHODS

Using stepwise calling on next-generation sequencing data from 499 patients with CTEPH referred to 3 centers between October 2006 and December 2021, CHIP mutations were identified. We associated CHIP with all-cause mortality in patients with CTEPH. To provide insights into potential mechanisms, the associations between CHIP and inflammatory markers were also determined.

RESULTS

In total, 47 (9.4%) patients with CTEPH carried at least 1 CHIP mutation at a variant allele frequency of ≥2%. The most common mutations were in DNMT3A, TET2, RUNX1, and ASXL1. During follow-up (mean, 55 months), deaths occurred in 22 (46.8%) and 104 (23.0%) patients in the CHIP and non-CHIP groups, respectively (P<0.001, log-rank test). The association of CHIP with mortality remained robust in the fully adjusted model (hazard ratio, 2.190 [95% CI, 1.257-3.816]; P=0.006). Moreover, patients with CHIP mutations showed higher circulating interleukin-1β and interleukin-6 and lower interleukin-4 and IgG galactosylation levels.

CONCLUSIONS

This is the first study to show that CHIP mutations occurred in 9.4% of patients with CTEPH are associated with a severe inflammatory state and confer a poorer prognosis in long-term follow-up.

[Pulmonary Hypertension and Polycythemia vera]

INTRODUCTION

 Chronic myeloproliferative diseases are rare causes of PH class 5 according to Nice classification 2018. The present case reports show different courses, on the one hand with a primary manifestation of a PH and subsequently a PV, on the other hand with the development of a PH in the context of a PV.

CASE REPORTS

 1) At first contact, a 75-year-old female patient who complained progressive dyspnea and had evidence of stress-PH in the right heart catheter. During the course she developed a resting PH of up to 70 mmHg systolic despite initial monotherapy and subsequent dual therapy for PH. After 5 years she had the diagnosis of polycythemia vera, treated with hydroxycarbamide and subsequent phlebotomies. In the further course increasing cardiac decompensation and death. 2) 74-year-old female patient at the time of diagnosis of chronic megakaryocytic-granulocytic myelosis. After 7 years, evidence of polycythemia vera (V617F mutation in the JAK2 gene), a monoclonal gammopathy. In the case of splenomegaly, irradiation of the spleen was carried out and, after 1 year, therapy with ruxolitinib was started. After another 2 years, with increasing dyspnea, pulmonary hypertension (CTEPH) with a PA-mean of 43 mmHg and a PVR of 4.5 WE were detected. With anticoagulation and riociguat therapy exercise capacity and PA pressures were only temporarily improved. Within 1 year restrictive ventilation, hypoxemia, heart failure (EF 45 %) with leading right heart decompensation and cardiorenal syndrome developed. Dialysis showed only short-term recompensation, and the patient died.

DISCUSSION

 The case reports are characterized by a combination of PV and PH, with different temporal sequence, as well as only a low influence of PH-specific therapy, with subsequent progressive cardiac decompensation. Thus, they reflect the different etiologies, clinical manifestations, and the low therapeutic influence of PH in myeloproliferative disorders. The value of PH-specific therapy remains unclear, especially in view of different pathomechanisms in the genesis of PH.

CONCLUSION

 Patients with myeloproliferative diseases require screening for PH. In the course of PH, myeloproliferative disease can unmask or develop. The therapeutic influence on PH is limited.