Platelet count trends and response to fondaparinux in a cohort of heparin-induced thrombocytopenia suspected patients after pulmonary endarterectomy.

A definitive diagnosis of heparin-induced thrombocytopenia (HIT) is difficult to make, especially in patients undergoing cardiac surgery. In this retrospective cohort study, we assessed the platelet count trends and the response to fondaparinux in a population of patients of suspected HIT after pulmonary endarterectomy (PEA). Patients enrolled in this study were over the age of 18 years, and survived longer than 7 days after PEA between January 1, 2011 and December 31, 2015. HIT likelihood was assessed by the 4 T's score and interpreted by our institutional algorithm. 54 patients were operated, and 49 patients met the inclusion criteria. Six patients met the criteria for suspected HIT and were treated with fondaparinux until the platelet recovered. No significant difference was observed of clinical characteristics between intermediate to high HIT likelihood patients (HIT SUSPECTED) and low HIT likelihood patients (NO HIT SUSPECTED). HIT SUSPECTED patients reached platelet count lowest later (about 5.5 days after PEA), while NO HIT SUSPECTED patients is about 4.0 days after PEA. Percentage of platelet counts decrease (> 50%) was larger than NO HIT SUSPECTED patients (< 50%). There was no difference in mortality or residual pulmonary hypertension between HIT SUSPECTED and NO HIT SUSPECTED patients. Two HIT SUSPECTED patients who used heparin after PEA died, the other four survived by replacing heparin or low molecular weight heparin with fondaparinux. Suspected HIT patients should be surveilled carefully. Platelet counts trends may have some hints in the prevention of HIT. Fondaparinux may be effective for patients with suspected HIT.

Analysis of clinical features between active and inactive patients of Takayasu's arteritis with pulmonary arteries involvement.

BACKGROUND: The aim of this study was to investigate the clinical characteristics of patients between active and inactive Takayasu's arteritis with pulmonary artery involvement (PTA) and to identify better markers of disease activity in these patients. METHODS: Sixty-four PTA patients in Beijing Chao-yang hospital (2011 to 2021) were included. According to National Institutes of Health criteria, 29 patients were in active stage and 35 were in inactive stage. Their medical records were collected and analyzed. RESULTS: Compared with inactive group, patients in active group were younger. More patients in active stage presented fever (41.38% vs 5.71%), chest pain (55.17% vs 20%), increased C-reactive protein (2.91 vs 0.46 mg/L), erythrocyte sedimentation rate (35.0 vs 9 mm/h), and platelet count (291 vs 221 × 109/L). Pulmonary artery wall thickening was more common in active group (51.72% vs 11.43%). These parameters were restored after treatment. The incidence of pulmonary hypertension was comparable between groups (34.48% vs 51.43%), but patients in active group had lower pulmonary vascular resistance (PVR) (361.0 vs 891.0 dyn·s·cm-5) and higher cardiac index (2.76 ± 0.72 vs 2.01 ± 0.58 L/min/m2). On multivariate logistic regression analysis, chest pain [odds ratio (OR) 9.37, 95%CI (1.98-44.38), P = 0.005], increased platelet count (>242.5 × 109/L) [OR 9.03, 95%CI (2.10-38.87), P = 0.003] and pulmonary artery wall thickening [OR 7.08, 95%CI (1.44-34.89), P = 0.016] were independently associated with disease activity. CONCLUSION: Chest pain, increased platelet count, and pulmonary artery wall thickening are potential new indicators of disease activity in PTA. Patients in active stage may have lower PVR and better right heart function.

Long-term Outcomes and Predictors of Chronic Thromboembolic Pulmonary Hypertension After Pulmonary Endarterectomy.

BACKGROUND: Pulmonary endarterectomy (PEA) is the preferred treatment for CTEPH patients which can significantly improve symptoms and pulmonary hemodynamics. Therefore, this retrospective study evaluated the long-term outcomes after pulmonary endarterectomy (PEA) and analyze the predictors of long-term outcomes for chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: From 2002-2020, 76 CTEPH patients successfully discharged after PEA in Beijing Chaoyang Hospital were followed-up by scheduled clinical visits or telephone interviews. The follow-up time lasted for 18 years and median time was 7.29 years. RESULTS: The survival rate at 1,3,5,10,15 years postoperatively was 100.00%, 97.10%, 95.40%, 89.80% and 82.90%, respectively. Multivariate logistics regression analysis showed that postoperative mPAP (hazard ratio: 1.144; 95%confidence interval: 1.018-1.285; P = 0.023) was associated with a higher risk of late death, right atrium right and left diameters (hazard ratio: 1.113; 95%confidence interval, 1.006-1.231; P = 0.038) were associated with a higher risk of major adverse events. CONCLUSION: Pulmonary endarterectomy is an effective way to treat CTEPH. Long-term outcome is excellent for patients who undergoing pulmonary endarterectomy who survived from peri-operation time. Postoperative mPAP is a significant prognostic factor for long-term death and right atrium right and left diameters is a significant prognostic factor for major adverse events. That shows patients with high postoperative mPAP and right atrium right and left diameter should be followed up closely.

Fibrinogen Aα Thr312Ala polymorphism specifically contributes to chronic thromboembolic pulmonary hypertension by increasing fibrin resistance.

BACKGROUND: Polymorphisms are associated with chronic thromboembolic pulmonary hypertension (CTEPH) and pulmonary thromboembolism (PTE), but no polymorphism specific to CTEPH but not PTE has yet been reported. Fibrin resistance is associated with CTEPH, but the mechanism has not been elucidated. METHODS: Polymorphisms were analyzed in 101 CTEPH subjects, 102 PTE subjects and 108 healthy controls by Massarray or restriction fragment length polymorphism (RFLP). Plasmin-mediated cleavage of fibrin was characterized in 69 subjects (29 with CTEPH, 21 with PTE and 19 controls). RESULTS: Genotype frequencies and allele frequencies of fibrinogen Aα Thr312Ala were significantly higher in CTEPH subjects than in controls and PTE subjects, while there was no difference between PTE subjects and controls. The odd ratio (OR 2.037) and 95% confidence interval (95% CI, 1.262-3.289) showed that Thr312Ala polymorphism was a risk factor for CTEPH but not PTE. Fibrin from CTEPH subjects was more resistant to lysis than that from PTE subjects and controls. Fibrin resistance was significantly different between Aα Thr312Ala (A/G) genotypes within CTEPH subjects, and the fibrin with GG genotype was more resistant than that with AA and AG genotype. CONCLUSIONS: Fibrinogen Aα Thr312Ala (A/G) polymorphism was associated with CTEPH, but not PTE, suggesting that the fibrinogen Aα Thr312Ala polymorphism may act as a potential biomarker in identifying CTEPH from PTE. GG genotype polymorphism contributes to CTEPH through increasing fibrin resistance, implying that PTE subjects with fibrinogen Aα GG genotype may need long-term anticoagulation therapy.